Chapter 9: Nursing Care During Normal Pregnancy and Care of the Developing Fetus

Assessment for surfactant level is a primary estimation of fetal maturity. The purpose of surfactant is to: A) prevent alveoli from collapsing on expiration. B) increase lung resistance on inspiration. C) encourage immunologic competence of lung tissue. D) promote maturation of lung alveoli.

Ans: A Client Needs: Physiological Integrity: Physiological Adaptation Cognitive Level: Remember Page: 185 Feedback: Surfactant is a phospholipid that reduces surface tension; it prevents alveoli from collapsing on expiration.

. Amniotic fluid does not grow stagnant because: A) amniotic fluid is constantly formed by the amnion. B) amniotic fluid is constantly absorbed by the chorion. C) the fetal urine increases the bulk of amniotic fluid. D) amniotic fluid circulates through the chorionic villi.

Ans: A Client Needs: Physiological Integrity: Physiological Adaptation Cognitive Level: Understand Page: 179 Feedback: Amniotic fluid is formed by the amnion; a main portion of it is swallowed by the fetus.

The nurse is evaluating the fetal heart rate rhythm strip and determines that the amplitude varies with a rate 15 to 20 beats/min. What does this assessment finding indicate to the nurse about variability? A) Variability is absent. B) Variability is minimal. C) Variability is normal. D) Variability is marked.

Ans: C Client Needs: Safe, Effective Care Environment: Management of Care Client Needs 2: Health Promotion and Maintenance Cognitive Level: Analyze Feedback: Variability is absent when there is no peak-to-trough range detected. Variability is minimal when an amplitude range is detected but the rate is 5 beat/min or fewer. Variability is moderate or normal when an amplitude range is detected and the rate is 6 to 25 beat/min. Variability is marked when an amplitude range is detected and the rate is greater than 25 beat/min.

Ectoderm

Body Portions Formed Central nervous system (brain and spinal cord) Peripheral nervous system Skin, hair, nails, and tooth enamel Sense organs Mucous membranes of the anus, mouth, and nose Mammary glands

Endoderm

Body Portions Formed Lining of pericardial, pleura, and peritoneal cavities Lining of the gastrointestinal tract, respiratory tract, tonsils, parathyroid, thyroid, and thymus glands Lower urinary system (bladder and urethra)

Mesoderm

Body Portions Formed Supporting structures of the body (connective tissue, bones, cartilage, muscle, ligaments, and tendons) Upper portion of the urinary system (kidneys and ureters) Reproductive system Heart, lymph, and circulatory systems and blood cells

Nuchal Translucency

Children with a number of chromosome anomalies have unusual pockets of fat or fluid present in their posterior neck, which show on sonograms as nuchal translucency

Fertilization is never a certain occurrence because it depends on at least three separate factors:

Equal maturation of both sperm and ovum Ability of the sperm to reach the ovum Ability of the sperm to penetrate the zona pellucida and cell membrane and achieve fertilization -Out of this single-cell fertilized ovum (zygote), the future child and also the accessory structures needed for support during intrauterine life (placenta, fetal membranes, amniotic fluid, and umbilical cord) will form.

Stages of Fetal Development In just 38 weeks, a fertilized egg (ovum) matures from a single cell to a fully developed fetus ready to be born. Although different cultures or religions debate the point at which life begins, for ease of discussion, all agree fetal growth and development can be divided into three time periods:

Pre-embryonic (first 2 weeks, beginning with fertilization) Embryonic (weeks 3 through 8) Fetal (from week 8 through birth)

Embryonic and Fetal Structures

The placenta and membranes, which will serve as the fetal lungs, kidneys, and digestive tract in utero as well as help provide protection for the fetus, begin growth in early pregnancy in coordination with embryo growth.

Conceptus

Time Period:Developing embryo and placental structures throughout pregnancy

Fetus

Time Period:From 5-8 weeks until term

Zygote

Time Period:From fertilization to implantation

Embryo

Time Period:From implantation to 5-8 weeks

Ovum

Time Period:From ovulation to fertilization

Age of viability

Time Period:The earliest age at which fetuses survive if they are born is generally accepted as 24 weeks or at the point a fetus weighs more than 500-600 g

Naegele's Rule

To calculate the date of birth by this rule, count backward 3 calendar months from the first day of a woman's last menstrual period and add 7 days. For example, if the last menstrual period began May 15, you would count back 3 months (April 15, March 15, February 15) and add 7 days, to arrive at the predicted date of birth as February 22.

SAFETY Liz Calhorn tells the nurse she is worried her baby will be born with a congenital heart disease. What assessment of the umbilical cord at birth would be most important to help detect congenital heart defects? a. Assessing whether the pH of the Wharton jelly is higher than 7.2 b. Assessing whether the umbilical cord has two arteries and one vein c. Measuring the length of the cord to be certain it is longer than 3 ft d. Determining that the umbilical cord is neither green nor yellow stained

b. Assessing whether the umbilical cord has two arteries and one vein

Biparietal Diameter Ultrasonography may be used to predict fetal maturity by measuring the

biparietal diameter (side-to-side measurement) of the fetal head. In 80% of pregnancies in which the biparietal diameter of the fetal head is 8.5 cm or greater, it can be predicted the infant will weigh more than 2,500 g (5.5 lb) at birth or is at a fetal age of 40 weeks.

NURSING DIAGNOSIS Common nursing diagnoses related to growth and development of the fetus focus on the pregnant woman and the family as well as the fetus. Examples might include:

-Readiness for enhanced knowledge related to usual fetal development -Anxiety related to lack of fetal movement -Deficient knowledge related to the need for good prenatal care for healthy fetal well-being

IMPLEMENTATION Most expectant parents are interested in learning about how mature their fetus is at various points in pregnancy as this helps them visualize their expected newborn. This, in turn, helps them to understand the importance of implementing healthy behaviors, such as

-eating well and avoiding substances that may be dangerous to a fetus such as recreational drugs. -Viewing a sonogram and learning the fetal sex is a big step toward helping initiate bonding between the parents and the infant. Remember each woman's pregnancy is unique to her; be certain implementations are individualized for each woman for the best chance of outcome success.

The number of veins and arteries in the cord is always assessed and recorded at birth because about

1% to 5% of infants are born with a cord that contains only a single vein and artery. Of these infants, 15% to 20% are found to have accompanying chromosomal disorders or congenital anomalies, particularly of the kidney and heart

Set up for non-stress test in pregnancy

1. Position the woman and attach both a fetal heart rate and a uterine contraction monitor. 2.Instruct the woman to push the button attached to the monitor (similar to a call bell) whenever she feels the fetus move. This will create a dark mark on the paper tracing at these times. 3.When the fetus moves, the fetal heart rate should increase approximately 15 beats/min and remain elevated for 15 seconds. It should decrease to its average rate again as the fetus quiets 4. If no increase in beats per minute is noticeable on fetal movement, further testing may be necessary to rule out poor oxygen perfusion of the fetus.

OUTCOME EVALUATION An outcome evaluation related to fetal growth and development usually focuses on determining whether a woman or family has made any changes in lifestyle necessary to ensure fetal growth and whether a woman voices confidence that her baby is healthy and growing. Examples of expected outcomes include:

1.Parents describe smoke-free living by next prenatal visit. 2.Patient records number of movements fetus makes during 1 hour daily. 3.Couple attends all scheduled prenatal visits. 4.Patient states she is looking forward to the birth of her baby.

The ability of the gastrointestinal tract to secrete enzymes essential for carbohydrate and protein digestion is mature at 36 weeks. However, amylase, an enzyme found in saliva and necessary for digestion of complex starches, does not mature until

3 months after birth. Many newborns have also not yet developed lipase, an enzyme needed for fat digestion (a reason breast milk is the best food for newborns because its digestion does not depend on these enzymes).

To provide enough blood for exchange, the rate of uteroplacental blood flow in pregnancy increases from about 50 ml/min at 10 weeks to

500 to 600 ml/min at term. No additional maternal arteries appear after the first 3 months of pregnancy; instead, to accommodate the increased blood flow, the arteries increase in size. The woman's heart rate, total cardiac output, and blood volume all increase to supply blood to the placenta

Implantation is an important step in pregnancy because as many as 50% of zygotes never achieve it. In these instances, the pregnancy ends as early as

8 to 10 days after conception, often before a woman is even aware she was pregnant. Occasionally, a small amount of vaginal spotting appears on the day of implantation because capillaries are ruptured by the implanting trophoblast cells. A woman who normally has a particularly scant menstrual flow could mistake implantation bleeding for her menstrual period. If this happens, the predicted date of birth of her baby (based on the time of her last menstrual period) will be calculated 4 weeks late.

Implantation, or contact between the growing structure and the uterine endometrium, occurs approximately

8 to 10 days after fertilization. About 8 days after ovulation, the blastocyst sheds the last residues of the corona and zona pellucida, brushes against the rich uterine endometrium (in the second [secretory] phase of the menstrual cycle), and settles down into its soft folds.

At term, the amount of amniotic fluid has grown so much it ranges from

800 to 1,200 ml. If for any reason the fetus is unable to swallow (esophageal atresia or anencephaly are the two most common reasons), excessive amniotic fluid or hydramnios (more than 2,000 ml in total or pockets of fluid larger than 8 cm on ultrasound) will result -Hydramnios may also occur in women with diabetes because hyperglycemia causes excessive fluid shifts into the amniotic space

At birth, an infant's oxygen saturation level is

95% to 100% and pulse rate is 80 to 140 beats/min. Because there is a great deal of mixing of blood in the fetus, the oxygen saturation level of fetal blood reaches only about 80%.

ASSESSING FETAL WELL-BEING

A number of actions or procedures are helpful in detecting and documenting the fetus is not only growing but also apparently healthy

IMPLANTATION Once fertilization is complete, a zygote migrates over the next 3 to 4 days toward the body of the uterus, aided by the currents initiated by the muscular contractions of the fallopian tubes. During this time, mitotic cell division, or cleavage, begins. The first cleavage occurs at about 24 hours; cleavage divisions continue to occur at a rate of about one every 22 hours so by the time the zygote reaches the body of the uterus; it consists of 16 to 50 cells. Over the next 3 or 4 days, large cells tend to collect at the periphery of the ball, leaving a fluid space surrounding an inner cell mass. At this stage, the structure is termed a ?

blastocyst. The cells in the outer ring are trophoblast cells. They are the part of the structure that will later form the placenta and membranes. The inner cell mass (embryoblast cells) is the portion of the structure that will form the embryo.

Patient-Centered Care Liz Calhorn is scheduled to have an ultrasound examination and the nurse wants to ensure that she understands and is prepared for this procedure to mitigate her anxiety. What instruction would the nurse give her before her examination? a. "Use the restroom immediately before the procedure to reduce your bladder size." b. "The intravenous fluid used to dilate your uterus does not hurt the fetus." c. "You will need to drink at least three glasses of water before the procedure." d. "You can have medicine for the pain of any contractions caused by the test."

c. "You will need to drink at least three glasses of water before the procedure."

RESPIRATORY SYSTEM At the third week of intrauterine life, the respiratory and digestive tracts exist as a single tube. Like all body tubes, initially, this forms as a solid structure, which then

canalizes (i.e., hollows out). By the end of the fourth week, a septum begins to divide the esophagus from the trachea. At the same time, lung buds appear on the trachea.

ZYGOTE GROWTH As soon as conception has taken place, development proceeds in a

cephaloca udal (head-to-tail) direction; that is, head development occurs first and is followed by development of the middle and, finally, the lower body parts. This pattern of development continues after birth as shown by the way infants are able to lift up their heads approximately 1 year before they are able to walk.

Invasive Fetal Testing If a genetic or growth concern is identified by noninvasive measures, a number of invasive measures allow for more refined investigation. Examples include

chorionic villi sampling and amniocentesis

A decrease in amniotic fluid volume puts the fetus at risk for ?

compression of the umbilical cord with interference of nutrition as well as lack of room to exercise and maintain muscle tone. Between 28 and 40 weeks, the total pockets of amniotic fluid revealed by sonogram average 12 to 15 cm. An amount greater than 20 to 24 cm indicates hydramnios (i.e., excessive fluid, perhaps caused by inability of the fetus to swallow). An amount less than 5 to 6 cm indicates oligohydramnios (i.e., decreased amniotic fluid, perhaps caused by poor perfusion and kidney failure).

TEAMWORK & COLLABORATION Liz Calhorn, 18 years of age, asks how much longer her nurse practitioner will refer to the baby inside her as an embryo. To ensure team members use terms consistently, the nurse would want them to know the conceptus is classified as an embryo at what time? a. At the time of fertilization b. When the placenta forms c. From implantation until 20 weeks d. From implantation until 5 to 8 weeks

d. From implantation until 5 to 8 weeks

Amniotic Fluid Volume The amount of amniotic fluid present is yet another way to estimate fetal health because a portion of the fluid is formed by fetal kidney output. If a fetus is becoming so stressed in utero that circulatory and kidney function is failing, urine output and, consequently, the volume of amniotic fluid will ?

decrease.

The use of a fetoscopy, in which the fetus is visualized by inspection through a fetoscope (an extremely narrow, hollow tube inserted by amniocentesis technique), can be yet another way to assess fetal well-being. This method allows

direct visualization of both the amniotic fluid and the fetus .

The endometrium is now typically termed the decidua (the Latin word for "falling off") because it will be

discarded after birth of the child.

Blood flows from the umbilical vein to the ductus venosus, an accessory vessel that

discharges oxygenated blood into the fetal liver, and then connects to the fetal inferior vena cava so oxygenated blood is directed to the right side of the heart.

Until the seventh week of life, the diaphragm does not completely divide the thoracic cavity from the abdomen. This causes lung buds to

extend down into the abdomen, reentering the chest only as the chest's longitudinal dimension increases and the diaphragm becomes complete (at the end of the seventh week). If the diaphragm fails to close completely, the stomach, spleen, liver, or intestines may be pulled up into the thoracic cavity. This causes the child to be born with intestine present in the chest (i.e., diaphragmatic hernia), compromising the lungs and perhaps displacing the heart

hCG's purpose is to act as a.

fail-safe measure to ensure the corpus luteum of the ovary continues to produce progesterone and estrogen so the endometrium of the uterus is maintained

A fundal measurement much less than this suggests the fetus is

failing to thrive (e.g., intrauterine growth restriction), the pregnancy length was miscalculated, or an anomaly interfering with growth has developed. McDonald's rule becomes inaccurate during the third trimester of pregnancy because the fetus is growing more in weight than in height during this time.

If an X-carrying spermatozoon entered the ovum, the resulting child will have two X chromosomes and will be assigned

female at birth (XX).

alcohol perfuses across the placenta and may cause ???

fetal alcohol spectrum disorder (e.g., unusual facial features, low-set ears, and cognitive challenge). Because it's difficult to tell what quantity is "safe," pregnant women are advised to drink no alcohol during pregnancy to avoid these disorders

Maternal Serum for Pregnancy-Associated Plasma Protein A Pregnancy-associated plasma protein A (PAPP-A) is a protein secreted by the placenta; low levels in maternal blood are associated with

fetal chromosomal anomalies, including trisomies 13, 18, and 21 or small-for-gestational-age (SGA) babies. A high PAPP-A level may predict an LGA baby.

The liver is active throughout intrauterine life, functioning as a filter between the incoming blood and the

fetal circulation and as a deposit site for fetal stores such as iron and glycogen. Unfortunately, during intrauterine life, the fetal liver is unable to prevent recreational drugs or alcohol ingested by the mother from entering the fetal circulation and possibly causing birth anomalies

A nonstress test measures the response of the

fetal heart rate to fetal movement.

THE AMNIOTIC FLUID The major method of absorption, however, happens within the fetus. Because the fetus continually swallows the fluid, it is absorbed from the

fetal intestine into the fetal bloodstream. From there, it goes to the umbilical arteries and to the placenta and is exchanged across the placenta to the mother's bloodstream.

As a fetus practices breathing movements, surfactant mixes with amniotic fluid. Using an amniocentesis technique, an analysis of the lecithin/sphingomyelin (L/S) ratio in surfactant (whether lecithin or sphingomyelin is the dominant component) is a primary test of

fetal maturity. Respiratory distress syndrome, a severe breathing disorder, can develop if there is a lack of surfactant or it has not changed to its mature form at birth

The umbilical cord is formed from the .

fetal membranes, the amnion and chorion, and provides a circulatory pathway that connects the embryo to the chorionic villi of the placenta

Because the rate of blood flow through the cord is so rapid, it is unlikely a knot or twist in the cord will interfere with the

fetal oxygen supply. In about 20% of all births, a loose loop of cord is found around the fetal neck (nuchal cord) at birth

Biophysical Profile A biophysical profile combines five parameters

fetal reactivity, fetal breathing movements, fetal body movement, fetal tone, and amniotic fluid volum into one assessment. The fetal heart and breathing record measures short-term central nervous system function; the amniotic fluid volume helps measure long-term adequacy of placental function.

The healthy development of the unborn child, referred to as the

fetus, pregnancy can determine the health of the newborn, and health as a newborn is a positive predictor for health throughout the individual's life span

Placental transfer is dynamic, allowing all but a few substances to cross from the mother into the

fetus. Because almost all drugs are able to cross into the fetal circulation, it is important that a woman take no nonessential drugs (including alcohol and nicotine) during pregnancy

Because there is no need for the bulk of blood to pass through the lungs, the bulk of this blood is shunted as it enters the right atrium into the left atrium through an opening in the atrial septum called the

foramen ovale. From the left atrium, it follows the course of adult circulation into the left ventricle, then into the aorta, and out to body parts.

DIGESTIVE SYSTEM The digestive tract separates from the respiratory tract at about the

fourth week of intrauterine life and, after that, begins to grow extremely rapidly. Initially solid, the tract canalizes (hollows out) to become patent. -Atresia (blockage) or stenosis (narrowing) of the track are common fetal anomalies and develop if either the first or second canalization does not occur

TO HELP ENSURE FETAL HEALTH ASSESSMENT Assessing fetal growth throughout pregnancy, by measuring

fundal height and fetal heart rate, is important because these signs of fetal development provide guidelines for determining the well-being of a fetus. -For the expectant family, knowledge about fetal growth and development can help a woman understand some of the changes going on in her body as well as allow all family members to begin thinking about and accepting a new member to their family. For this reason, assessing fetal development at prenatal visits and conveying the findings are important, providing the family in as much detail as parents' request.

REPRODUCTIVE SYSTEM A child's sex is determined at the moment of conception by a spermatozoon carrying an X or a Y chromosome and can be ascertained as early as 8 weeks by chromosomal analysis or analysis of fetal cells in the mother's bloodstream. At about the sixth week after implantation, the

gonads (i.e., ovaries or testes) form. If testes form, testosterone is secreted, apparently influencing the sexually neutral genital duct to form other male organs (i.e., maturity of the wolffian, or mesonephric, duct). In the absence of testosterone secretion, female organs will form (i.e., maturation of the müllerian, or paramesonephric, duct).

After the 28th week of pregnancy, when the sympathetic nervous system matures, the heart rate stabilizes, and a consistent

heart rate of 110 to 160 beats/min is assessed.

Long-term variability reflects the state of the fetal sympathetic nervous system. On a rhythm strip, it is the differences in

heart rate that occur over the 20-minute time period. the heart rate in fetuses varies from 150 to 130 beats/min.

The walls of the umbilical cord arteries are lined with smooth muscle. When these muscles contract after birth, the cord arteries and vein are compressed to prevent

hemorrhage of the newborn through the cord. Because the umbilical cord contains no nerve supply, it can be clamped and cut at birth without discomfort to either the child or mother.

Fetal Circulation Fetal circulation differs from extrauterine circulation because the fetus derives oxygen and excretes carbon dioxide not from gas exchange in the lungs but from exchange in the placenta. Blood arriving at the fetus from the placenta is ?

highly oxygenated. This blood enters the fetus through the umbilical vein (which is still called a vein even though it carries oxygenated blood because the direction of the blood is toward the fetal heart).

Endocrine Function Besides serving as the source of oxygen and nutrients for the fetus, the syncytial (outer) layer of the chorionic villi develops into a separate and important

hormone-producing system.

In primiparas (i.e., women having their first baby), the fetus often sinks into the birth canal during the last 2 weeks of pregnancy, giving the mother a feeling the load she is carrying

is less. This event, termed lightening, is a fetal announcement that the fetus is in a ready position and birth is nearing.

If the woman has Rh-negative blood, Rho(D) immune globulin (RhIG; RhoGAM) is administered after the procedure to prevent fetal

isoimmunization or help ensure maternal antibodies will not form against any placental red blood cells that might have accidentally been released into the maternal bloodstream during the procedure.

Surfactant has two components:

lecithin and sphingomyelin. Early in the formation of surfactant, sphingomyelin is the chief component. At approximately 35 weeks, there is a surge in the production of lecithin, which then becomes the chief component by a ratio of 2:1.

Uterine perfusion and placental circulation are most efficient when the mother .

lies on her left side, as this position lifts the uterus away from the inferior vena cava, preventing blood from becoming trapped in the woman's lower extremities

Because this layer of cells disappears between the 20th and 24th week of pregnancy, this is why syphilis is not considered to have a high potential for fetal damage early in pregnancy, only after the point at which cytotrophoblast cells are no longer present. The layer appears to offer

little protection against viral invasion at any point, increasing the vulnerability of the fetus to viruses

If a Y-carrying spermatozoon fertilized the ovum, the resulting child will have an X and a Y chromosome and will be assigned

male at birth (XY).

if a woman should unintentionally take an androgen or an androgen-like substance during this stage of pregnancy, a child who is chromosomally female could appear more

male than female at birth. If deficient testosterone is secreted by the testes, both the müllerian (female) duct and the wolffian (male) duct could develop (i.e., pseudohermaphroditism, or intersex)

Estrogen Estrogen (primarily estriol) is produced as a second product of the syncytial cells of the placenta. Estrogen contributes to the woman's

mammary gland development in preparation for lactation and stimulates uterine growth to accommodate the developing fetus.

Human Chorionic Gonadotropin The first placental hormone produced, hCG, can be found in

maternal blood and urine as early as the first missed menstrual period (shortly after implantation has occurred) -The pregnant woman's blood serum will be completely negative for hCG within 1 to 2 weeks after birth. Finding no serum hCG after birth can be used as proof that placental tissue is no longer present.

hCG also may play a role in suppressing the

maternal immunologic response so placental tissue is not detected and rejected as a foreign substance. Because the structure of hCG is similar to that of luteinizing hormone of the pituitary gland, if the fetus is male, it exerts an effect on the fetal testes to begin testosterone production and maturation of the male reproductive tract

McDonald's rule, another symphysis-fundal height measurement (although, again, not documented to be thoroughly reliable), is an easy method of determining

midpregnancy growth. Typically, tape measurement from the notch of the symphysis pubis to over the top of the uterine fundus as a woman lies supine is equal to the week of gestation in centimeters between the 20th and 31st weeks of pregnancy (e.g., in a pregnancy of 24 weeks, the fundal height should be 24 cm)

A fundal height much greater than this standard suggests a

multiple pregnancy, a miscalculated due date, a large-for-gestational-age (LGA) infant, hydramnios (increased amniotic fluid volume), or possibly even gestational trophoblastic disease

The neurologic system seems particularly prone to insult during the early weeks of the embryonic period and can result in

neural tube disorders, such as a meningocele (i.e., herniation of the meninges), especially if there is lack of folic acid (which is contained in green leafy vegetables and pregnancy vitamins) All during pregnancy and at birth, the system is vulnerable to damage if anoxia should occur.

The complex structure of the kidneys gradually develops during intrauterine life and continues to mature for months afterward. The loop of Henle, for example, is not fully differentiated until the fetus is born. Glomerular filtration and concentration of urine in the newborn are still not efficient because the ability to concentrate urine is still

not mature at birth. Early in the embryonic stage of urinary system development, the bladder extends as high as the umbilical region, and there is an open lumen between the urinary bladder and the umbilicus. If this fails to close, (termed a patent urachus), this is revealed at birth by the persistent drainage of a clear, acid-pH fluid (urine) from the umbilicus

Implantation usually occurs high in the uterus on the posterior surface. If the point of implantation is low in the uterus, the growing placenta may

occlude the cervix and make birth of the child difficult (placenta previa) because the placenta can block the birth canal. .

Early in fetal life, as soon as the fetal kidneys become active, fetal urine adds to the quantity of the amniotic fluid. A disturbance of kidney function, therefore, may cause

oligohydramnios or a reduction in the amount of amniotic fluid. -The amniotic fluid index is measured, and it should be at least 5 cm. The vertical pocket of amniotic fluid should be greater than 2 cm

If any intestine remains outside the abdomen in the base of the cord, a congenital anomaly, termed

omphalocele, will be present at birth. A similar defect, gastroschisis, occurs when the original midline fusion that occurred at the early cell stage is incomplete

An umbilical cord contains only

one vein (carrying blood from the placental villi to the fetus) and two arteries (carrying blood from the fetus back to the placental villi).

Refer women and their families to

online resources for further information when appropriate. Helpful resources addressing pregnancy, birth, and postpartal care are available.

THE AMNIOTIC MEMBRANES The chorionic villi on the medial surface of the trophoblast (i.e., those that are not involved in implantation because they do not touch the endometrium) gradually thin until they become the chorionic membrane, the

outermost fetal membrane. The amniotic membrane, or amnion, forms beneath the chorion

As early as the 11th or 12th day after fertilization, miniature villi, resembling probing fingers and termed chorionic villi, reach out from the trophoblast cells into the uterine endometrium to begin formation of the

placenta. Chorionic villi have a central core consisting of connective tissue and fetal capillaries surrounded by a double layer of cells, which produce various placental hormones, such as hCG, somatomammotropin (human placental lactogen [hPL]), estrogen, and progesterone.

MUSCULOSKELETAL SYSTEM During the first 2 weeks of fetal life, cartilage prototypes provide

position and support to the fetus. Ossification of this cartilage into bone begins at about the 12th week and continues all through fetal life and into adulthood. ' Carpals, tarsals, and sternal bones generally do not ossify until birth is imminent.

A fetoscopy carries a small risk of

premature labor or amnionitis (infection of the amniotic fluid). To avoid infection, the woman may be prescribed antibiotic therapy after the procedure. The number of procedures performed by a fetoscopy is limited because of the manipulation involved and the ethical quandary of the mother's autonomy being compromised by fetal needs if further procedures are necessary such as asking the pregnant woman to undergo general anesthesia so the fetus can have surgery.

In contrast to the chorionic membrane, the second membrane (the amniotic membrane) not only offers support to amniotic fluid but also actually

produces the fluid. In addition, it produces a phospholipid that initiates the formation of prostaglandins, which may be the trigger that initiates labor.

Doppler ultrasonography measures the velocity at which

red blood cells in the uterine and fetal vessels travel. 1.Assessment of the blood flow through uterine blood vessels is helpful to determine the vascular resistance present in women with gestational diabetes or hypertension and whether resultant placental insufficiency is occurring. 2.Decreased velocity is an important predictor that uterine growth restriction will occur because it reveals that only a limited number of nutrients are able to reach the fetus

The most important purpose of amniotic fluid is to

shield the fetus against pressure or a blow to the mother's abdomen. Because liquid changes temperature more slowly than air, it also protects the fetus from changes in temperature. Another function is that it aids in muscular development, as amniotic fluid allows the fetus freedom to move. Finally, it protects the umbilical cord from pressure, thus protecting the fetal oxygen supply.

Human Placental Lactogen (Human Chorionic Somatomammotropin) hPL is a hormone with both growth-promoting and lactogenic (i.e., milk-producing) properties. It is produced by the placenta beginning as early as the

sixth week of pregnancy, increasing to a peak level at term. It promotes mammary gland (breast) growth in preparation for lactation in the mother. It also serves the important role of regulating maternal glucose, protein, and fat levels so adequate amounts of these nutrients are always available to the fetus.

Most women are aware alcohol ingestion can harm a fetus (e.g., fetal alcohol spectrum disorder) but many are not yet aware of fetal tobacco syndrome. This syndrome applies to the fetus of a woman who

smokes more than five cigarettes a day and who is born growth restricted (i.e., birth weight under 2,500 g at term). Smoking may also be a cause of ectopic (tubal) pregnancy as fallopian tubes may become irritated

All of the spermatozoa that reach the ovum cluster around its protective layer of corona cells. Hyaluronidase (a proteolytic enzyme) is released by the

spermatozoa and dissolves the layer of cells protecting the ovum. Under ordinary circumstances, only one spermatozoon is able to penetrate the cell membrane of the ovum. Once it penetrates the cell, the cell membrane changes composition to become impervious to other spermatozoa. An exception to this is the formation of gestational trophoblastic disease in which multiple sperm enter an ovum; this leads to abnormal zygote formation

Maternal Serum α-Fetoprotein AFP is a substance produced by the fetal liver that can be found in both amniotic fluid and maternal serum . The level is abnormally high if the fetus has an open ?

spinal or abdominal wall defect because the open defect allows more AFP to enter the mother's circulation than usual. Although the reason is unclear, the level is low if the fetus has a chromosomal defect such as Down syndrome. MSAFP levels begin to rise at 11 weeks gestation and then steadily increase until term. Traditionally assessed at the 15th week of pregnancy, between 85% and 90% of neural tube anomalies and 80% of babies with Down syndrome can be detected by this method

The middle layer, the cytotrophoblast or Langhans' layer, appears to have a second function to protect the growing embryo and fetus from certain infectious organisms such as the

spirochete of syphilis early in pregnancy.

Meconium, a collection of cellular wastes, bile, fats, mucoproteins, mucopolysaccharides, and portions of the vernix caseosa (i.e., the lubricating substance that forms on the fetal skin), accumulates in the intestines as early as the 16th week. Meconium is

sticky in consistency and appears black or dark green (obtaining its color from bile pigment). An important neonatal nursing responsibility is recording that a newborn has passed meconium as this rules out a stricture (noncanalization) of the anus

Magnetic Resonance Imaging Magnetic resonance imaging (MRI) is yet another way to assess a growing fetus. Because the technique apparently causes no harmful effects to the fetus or woman, MRI has the potential to replace or complement ultrasonography as a fetal assessment technique because it can identify ?

structural anomalies or soft tissue disorders -An MRI may be most helpful in diagnosing complications such as ectopic pregnancy or trophoblastic disease

If a woman lies on her back and the weight of the uterus compresses on the vena cava, known as vena cava syndrome, placental circulation can be so sharply reduced that

supine hypotension (i.e., very low maternal blood pressure and poor uterine circulation) can occur

All organ systems are complete, at least in a rudimentary form, at 8 weeks gestation (the end of the embryonic period). During this early time of organogenesis (organ formation), the growing structure is most vulnerable to invasion by

teratogens (i.e., any factor that affects the fertilized ovum, embryo, or fetus adversely, such as a teratogenic medicine; an infection such as toxoplasmosis; cigarette smoking; or alcohol ingestion)

Because of this rapid intestinal growth, by the sixth week of intrauterine life, the intestine becomes too large to be contained by

the abdomen. A portion of the intestine, therefore, is pushed into the base of the umbilical cord, where it remains until about the 10th week of intrauterine life or until the abdominal cavity has grown large enough to accommodate the bulky intestines. As intestine returns to the abdominal cavity at this point, it must rotate 180 degrees. Failure to do so can result in inadequate mesentery attachments, possibly leading to volvulus of the intestine in the newborn.

Specialized structures present in the fetus then shunt blood flow to first supply the most important organs of the body:

the liver, heart, kidneys, and brain.

A small amount of blood that returns to the heart via the vena cava does leave the right atrium by the adult circulatory route; that is, through the

tricuspid valve into the right ventricle and then into the pulmonary artery and lungs to service the lung tissue. However, the larger portion of even this blood is shunted away from the lungs through an additional structure, the ductus arteriosus, directly into the descending aorta.

As the majority of blood cells in the aorta become deoxygenated, blood is transported from the descending aorta through the

umbilical arteries (which are called arteries because they carry blood away from the fetal heart) back through the umbilical cord to the placental villi, where new oxygen exchange takes place.

The testes first form in the abdominal cavity and do not descend into the scrotal sac until the 34th to 38th week of intrauterine life. Because of this, many male preterm infants are born with

undescended testes. These boys need a follow-up to be certain their testes do descend when they reach what would have been the 34th to 38th week of gestational age because testicular descent does not always occur as readily in extrauterine life as it would have in utero. -Testes that do not descend (cryptorchidism) require surgery as they are associated with poor sperm production and possibly testicular cancer later in life

FERTILIZATION: THE BEGINNING OF PREGNANCY Fertilization (also referred to as conception and impregnation) is the

union of an ovum and a spermatozoon. This usually occurs in the outer third of a fallopian tube, termed the ampullar portion.

Make certain the woman knows fetal movements do

vary, especially in relation to sleep cycles, her activity, and the time since she last ate. Otherwise, she can become unduly worried her fetus is in jeopardy when the fetus is asleep or just having an inactive time.

URINARY SYSTEM Although rudimentary kidneys are present as early as the end of the fourth week of intrauterine life, the presence of kidneys does not appear to be essential for life before birth because the placenta clears the fetus of

waste products. Urine, however, is formed by the 12th week and is excreted into the amniotic fluid by the 16th week of gestation. At term, fetal urine is being excreted at a rate of up to 500 ml/day. An amount of amniotic fluid less than usual (oligohydramnios) suggests fetal kidneys are not secreting adequate urine and that there is a kidney, ureter, or bladder disorder

Placental Grading for Maturity Placentas can be graded by ultrasound based on the particular amount of calcium deposits present in the base. Placentas are graded as:

• 0: between 12 and 24 weeks • 1: 30 to 32 weeks • 2: 36 weeks • 3: 38 weeks (Because fetal lungs are apt to be mature by 38 weeks, a grade 3 placenta suggests the fetus is mature.)

Fetal Growth As a fetus grows, the uterus expands to accommodate its size. Although not evidence grounded, typical fundal (top of the uterus) measurements are:

• Over the symphysis pubis at 12 weeks • At the umbilicus at 20 weeks • At the xiphoid process at 36 weeks

Assessment of Fetal Growth and Development Tests for fetal growth and development are commonly done for a variety of reasons, including to:

• Predict the outcome of the pregnancy • Manage the remaining weeks of the pregnancy • Plan for possible complications at birth • Plan for problems that may occur in the newborn infant • Decide whether to continue the pregnancy • Find conditions that may affect future pregnancies' -Both fetal growth and development can be compromised if a fetus has a metabolic or chromosomal disorder that interferes with normal growth, if the supporting structures such as the placenta or cord do not form normally, or if environmental influences such as the nicotine in cigarettes causes fetal growth restriction (including testes growth in a male fetus)

Other important respiratory developmental milestones include:

• Spontaneous respiratory practice movements begin as early as 3 months gestation and continue throughout pregnancy. • Specific lung fluid with a low surface tension and low viscosity forms in alveoli to aid in expansion of the alveoli at birth; it is rapidly absorbed shortly after birth. •Surfactant, a phospholipid substance, is formed and excreted by the alveolar cells of the lungs beginning at approximately the 24th week of pregnancy. This decreases alveolar surface tension on expiration, preventing alveolar collapse and improving the infant's ability to maintain respirations in the outside environment at birth

ENDOCRINE SYSTEM

• The fetal pancreas produces insulin needed by the fetus (insulin is one of the few substances that does not cross the placenta from the mother to the fetus). • The thyroid and parathyroid glands play vital roles in fetal metabolic function and calcium balance. • The fetal adrenal glands supply a precursor necessary for estrogen synthesis by the placenta.

End of Fourth Gestational Week

• The length of the embryo is about 0.75 cm; weight is about 400 mg. • The spinal cord is formed and fused at the midpoint. • The head is large in proportion and represents about one third of the entire structure. • The rudimentary heart appears as a prominent bulge on the anterior surface. • Arms and legs are bud-like structures; rudimentary eyes, ears, and nose are discernible.

End of 16th Gestational Week

• The length of the fetus is 10 to 17 cm; weight is 55 to 120 g. • Fetal heart sounds are audible by an ordinary stethoscope. • Lanugo is well formed. • Both the liver and pancreas are functioning. • The fetus actively swallows amniotic fluid, demonstrating an intact but uncoordinated swallowing reflex; urine is present in amniotic fluid. • Sex can be determined by ultrasonography.

End of 20th Gestational Week

• The length of the fetus is 25 cm; weight is 223 g. • Spontaneous fetal movements can be sensed by the mother. • Antibody production is possible. • Hair, including eyebrows, forms on the head; vernix caseosa begins to cover the skin. • Meconium is present in the upper intestine. • Brown fat, a special fat that aids in temperature regulation, begins to form behind the kidneys, sternum, and posterior neck. • Passive antibody transfer from mother to fetus begins. • Definite sleeping and activity patterns are distinguishable as the fetus develops biorhythms that will guide sleep/wake patterns throughout life.

End of 24th Gestational Week (Second Trimester)

• The length of the fetus is 28 to 36 cm; weight is 550 g .• Meconium is present as far as the rectum. • Active production of lung surfactant begins. • Eyelids, previously fused since the 12th week, now open; pupils react to light. • Hearing can be demonstrated by response to sudden sound. • When fetuses reach 24 weeks, or 500 to 600 g, they have achieved a practical low-end age of viability if they are cared for after birth in a modern intensive care nursery.

End of 28th Gestational Week

• The length of the fetus is 35 to 38 cm; weight is 1,200 g. • Lung alveoli are almost mature; surfactant can be demonstrated in amniotic fluid. • Testes begin to descend into the scrotal sac from the lower abdominal cavity. • The blood vessels of the retina are formed but thin and extremely susceptible to damage from high oxygen concentrations (an important consideration when caring for preterm infants who need oxygen).

End of 32nd Gestational Week

• The length of the fetus is 38 to 43 cm; weight is 1,600 g. • Subcutaneous fat begins to be deposited (the former stringy, "little old man"appearance is lost). • Fetus responds by movement to sounds outside the mother's body. • An active Moro reflex is present. • Iron stores, which provide iron for the time during which the neonate will ingest only breast milk after birth, are beginning to be built. • Fingernails reach the end of fingertips.

End of 36th Gestational Week

• The length of the fetus is 42 to 48 cm; weight is 1,800 to 2,700 g (5 to 6 lb). • Body stores of glycogen, iron, carbohydrate, and calcium are deposited. • Additional amounts of subcutaneous fat are deposited. • Sole of the foot has only one or two crisscross creases compared with a full crisscross pattern evident at term. • Amount of lanugo begins to diminish. • Most fetuses turn into a vertex (head down) presentation during this month.

End of 40th Gestational Week (Third Trimester)

• The length of the fetus is 48 to 52 cm (crown to rump, 35 to 37 cm); weight is 3,000 g (7 to 7.5 lb). • Fetus kicks actively, sometimes hard enough to cause the mother considerable discomfort. • Fetal hemoglobin begins its conversion to adult hemoglobin. • Vernix caseosa starts to decrease after the infant reaches 37 weeks gestation and may be more apparent in the creases than the covering of the body as the infant approaches 40 weeks or more gestational age. • Fingernails extend over the fingertips. • Creases on the soles of the feet cover at least two thirds of the surface.

End of 12th Gestational Week (First Trimester)

• The length of the fetus is 7 to 8 cm; weight is about 45g. • Nail beds are forming on fingers and toes. • Spontaneous movements are possible, although they are usually too faint to be felt by the mother. • Some reflexes, such as the Babinski reflex, are present. • Bone ossification centers begin to form. • Tooth buds are present. • Sex is distinguishable on outward appearance. • Urine secretion begins but may not yet be evident in amniotic fluid. • The heartbeat is audible through Doppler technology.

End of Eighth Gestational Week

• The length of the fetus is about 2.5 cm (1 in.); weight is about 20 g. • Organogenesis is complete. • The heart, with a septum and valves, beats rhythmically. • Facial features are definitely discernible; arms and legs have developed. • External genitalia are forming, but sex is not yet distinguishable by simple observation. • The abdomen bulges forward because the fetal intestine is growing so rapidly. • A sonogram shows a gestational sac, which is diagnostic of pregnancy

Immediately after penetration of the ovum, the chromosomal material of the ovum and spermatozoon fuse to form a

zygote. Because the spermatozoon and ovum each carried 23 chromosomes (22 autosomes and 1 sex chromosome), the fertilized ovum has 46 chromosomes.

THE PLACENTA The placenta (Latin for "pancake," which is descriptive of its size and appearance at term) grows from a few identifiable trophoblastic cells at the beginning of pregnancy to an organ

15 to 20 cm in diameter and 2 to 3 cm in depth, covering about half the surface area of the internal uterus at term

Before an ultrasound examination, be certain a woman has received a good

explanation of what the procedure will be like and reassurance that the process does not involve X-rays and so will be safe for the fetus . This means it is also safe for the father of the child to remain in the room during the test and see the images as well.

Progesterone Estrogen is often referred to as the "hormone of women," and progesterone as the

"hormone that maintains pregnancy." progesterone is necessary to maintain the endometrial lining of the uterus during pregnancy. It is present in maternal serum as early as the fourth week of pregnancy as a result of the continuation of the corpus luteum. After placental production begins (at about the 12th week), the level of progesterone rises progressively during the remainder of the pregnancy. This hormone also appears to reduce the contractility of the uterus during pregnancy, thus preventing premature labor.

HEALTH HISTORY Ask the mother specifically about:

1.any prepregnancy illnesses such as gestational diabetes or heart disease because these both can interfere with fetal growth. 2.Ask about any drugs a woman takes; for instance, common drugs taken for recurrent seizures can be teratogenic and therefore pose a risk in pregnancy 3.. Inquire about nutritional intake because if a woman is not eating a well-balanced diet, she may not be taking in enough nutrients for fetal growth 4.Be certain to also ask about personal habits such as cigarette smoking, both prescription and recreational drug use, alcohol consumption, and exercise because all of these may influence glucose/insulin balance and fetal growth. 5.Asking if a woman has had any exposure to teratogens can reveal exposure to such substances as chemicals, paint fumes, cleaning products, poor air quality, or a loud noise level 6.Asking about unintentional injuries or intimate partner violence can help reveal whether the pregnant woman and fetus could have suffered any trauma from these sources (e.g., intimate partner violence tends to increase during pregnancy because of the stress a pregnancy can create)

Fetal Hemoglobin Fetal hemoglobin differs from adult hemoglobin in several ways. It has a different :

1.composition (two α and two γ chains compared with two α and two β chains of adult hemoglobin). 2.It is also more concentrated and has greater oxygen affinity, two features that increase its efficiency. 3. Because hemoglobin is more concentrated, a newborn's hemoglobin level is about 17.1 g/100 ml compared with a normal adult level of 11 g/100 ml; a newborn's hematocrit is about 53% compared with a normal adult level of 45%.

The sound waves reflect best if the uterus can be held stable so it is helpful if the woman has a

1.full bladder at the time of the procedure. To ensure this, ask her to drink a full glass of water every 15 minutes beginning 90 minutes before the procedure and to not void until after the procedure. 2.Help the woman up to an examining table and drape her for modesty, but with her abdomen exposed. 3.To prevent supine hypotension syndrome, place a towel under her right buttock to tip her body slightly so the uterus will roll away from the vena cava. 4.A gel is then applied to her abdomen to improve the contact of the transducer. Be certain the gel is at room temperature or even slightly warmer or it may cause uncomfortable uterine cramping. The transducer is then applied to her abdomen and moved both horizontally and vertically until the uterus and its contents are fully scanned

PHYSICAL EXAMINATION A physical examination of the mother is the second step in evaluating fetal health. Assess:

1.maternal weight and general appearance because both obesity and underweight are clues that the mother's nutrition may not be adequate for sound fetal growth 2. Bruises may indicate intimate partner violence that could have bruised the fetus as well. 3.An elevated blood pressure may be the beginning of hypertension of pregnancy, which can restrict fetal growth

Although the long-term effects of ultrasound are not yet known, the technique appears to be safe for both mother and fetus and causes no discomfort to the fetus. Usually, the only discomfort for the woman is the ?

1.messiness of the contact lubrication and a strong desire to void before the scan is completed. Taking home a photograph of the sonographic image can enhance bonding because it is proof the pregnancy exists and the fetus appears well. 2.As desirable as it is, however, caution women against having ultrasound images done just for the purpose of having "keepsake" photographs. Commercial firms offering these services are not well regulated, and their equipment may be outdated and unsafe

Rhythm Strip Testing The term "rhythm strip testing" refers to an assessment of fetal well-being and assesses the fetal heart rate for a normal baseline rate. For this, help the woman into a

1.semi-Fowler's position (either in a comfortable lounge chair or on an examining table or bed with an elevated backrest) to prevent her uterus from compressing the vena cava and causing supine hypotension syndrome during the test. 2.Attach an external fetal heart rate monitor abdominally . 3.Record the fetal heart rate for 20 minutes. The baseline reading refers to the average rate of the fetal heartbeat. Variability denotes the small changes in rate that occur from second to second if the fetal parasympathetic nervous system is receiving adequate oxygen and nutrients.

Nursing responsibilities for testing assessment procedures include

1.verifying that a signed consent form has been obtained as needed (which is necessary if the procedure poses any risk to the mother or fetus that would not otherwise be present), 2.being certain the woman and her support person are aware of what the procedure will entail and any potential risks, 3.preparing the woman physically and psychologically, 4.providing support during the procedure, assessing both fetal and maternal responses during and after the procedure, 5. providing any necessary follow-up care, and managing equipment and specimens. -Providing follow-up care may include being certain a couple understands the results of a test and how to interpret it. When a result is positive, parents feel assured their infant is growing well. When results are not encouraging, a couple may experience a mixture of emotions.

Fetal Heart Rate Fetal heart sounds can be heard and counted as early as the

10th to 11th week of pregnancy by the use of an ultrasound Doppler technique . This is done routinely at every prenatal visit past 10 weeks.

A normal fetal heart rate is

110 to 160 beats/min, supplying needed oxygen to cells.

A fetus can be seen to move on ultrasonography as early as the

11th week, although the mother usually does not feel this movement (quickening) until 16 to 20 weeks of gestation. It is usually felt earlier in multigravida women.

Rhythm strip testing requires a woman to remain in a fairly fixed position for

20 minutes. Keep her well informed of the importance and purpose of the test and be certain she understand the meaning of the results after the test

Once the mature ovum is released (i.e., ovulation), fertilization must occur fairly quickly because an ovum is capable of fertilization for only about

24 hours (48 hours at the most). After that time, it atrophies and becomes nonfunctional. Because the functional life of a spermatozoon is also about 48 hours, possibly as long as 72 hours, the total critical time span during which sexual relations must occur for fertilization to be successful is about 72 hours (48 hours before ovulation plus 24 hours afterward).

A pregnant patient is directed to perform a daily fetal movement count. What should the nurse instruct the patient about this count? Select all that apply. A) Lie down to do the count after eating a meal. B) Count only movements that are strong enough to hurt. C) Report if no movement is felt for any half-hour period. D) Choose a different time frame each day to count movements. E) Count fetal movements until a total of 10 are counted and record the time.

Ans: A, E Client Needs: Safe, Effective Care Environment: Management of Care Client Needs 2: Health Promotion and Maintenance Cognitive Level: Apply Feedback: A healthy fetus moves at about 10 times per hour. The nurse should instruct the patient to lie in a left recumbent position after a meal, observe and record the number of fetal movements or kicks the fetus makes until 10 movements are counted, and record the time. If an hour passes without 10 movements, the patient should walk around a little and try a count again. If 10 movements cannot be felt in a second 1-hour period, the patient should telephone the primary health care provider.

The fetal-assessment technique of a rhythm strip refers to: A) a fetal EKG, because it is effected by glucose stimulation. B) a tracing of fetal heart rate and pattern. C) the rhythm of fetal heart rate compared to maternal pulse. D) the response of fetal heart rate to oxytocin-stimulated contractions.

Ans: B Client Needs: Health Promotion and Maintenance Cognitive Level: Remember Page: 176 Feedback: Rhythm-strip testing is recording the fetal heart rate and pattern by an external monitor.

On what day during pregnancy does the embryo implant on the uterine surface? A) the 14th day of a "typical" menstrual cycle B) eight days after ovulation C) ten days after the start of the menstrual flow D) four days after ovulation

Ans: B Client Needs: Physiological Integrity: Physiological Adaptation Cognitive Level: Remember Page: 177 Feedback: After floating free in the uterine cavity for about 4 days, the zygote implants on the uterine surface on about the 22nd day; thereafter it is termed an embryo.

Implantation generally occurs at which place on the uterus? A) the lower anterior surface B) the upper posterior surface C) directly over the cervical os D) directly over an opening to a fallopian tube

Ans: B Client Needs: Physiological Integrity: Physiological Adaptation Cognitive Level: Remember Page: 179 Feedback:Implantation occurs most commonly on the upper posterior surface of the uterus. This position allows the fetus to deliver before the placenta

Which precaution should the nurse take with a pregnant woman following an amniocentesis? A) Remind her not to raise her head for 4 hours. B) Assess fetal heart rate and possible uterine contractions. C) Perform a vaginal examination for a ferning pattern. D) Assess for increased abdominal distention.

Ans: B Client Needs: Physiological Integrity: Reduction of Risk Potential Cognitive Level: Apply Feedback: Because amniocentesis is an invasive procedure, there is a risk that it might initiate uterine contractions. Assessing for contractions postprocedure is important to safeguard the pregnancy.

A fetus is capable of producing antibodies. The finding of IgM antibodies in an infant at birth implies that: A) antibodies were transferred to the fetus during pregnancy. B) the fetus contracted an infection during intrauterine life. C) the fetus's liver has reached developmental maturity. D) the mother contracted an infection during pregnancy.

Ans: B Client Needs: Physiological Integrity: Reduction of Risk Potential Cognitive Level: Apply Page: 185 Feedback: Because IgM antibodies are too large to cross the placenta, the only way they could be present in a fetus is if they were produced by the fetus in response to invading antigens (Toxoplasma gondii, which causes toxoplasmosis).

During a physical assessment, the nurse palpates a pregnant patient's fundus at the level of the umbilicus. What statement should the nurse make to the patient about this assessment finding? A) "You are at 12 weeks of your pregnancy." B) "You are at 20 weeks of your pregnancy." C) "You are at 36 weeks of your pregnancy." D) "You can go into labor at any time now."

Ans: B Client Needs: Safe, Effective Care Environment: Management of Care Client Needs 2: Health Promotion and Maintenance Cognitive Level: Apply Feedback: As a fetus grows, the uterus expands to accommodate its size. Typical fundal measurements are over the symphysis pubis at 12 weeks, at the umbilicus at 20 weeks, and at the xiphoid process at 36 weeks. The patient will not be going into labor very soon.

The nurse teaches the importance of avoiding nonessential substances to a young adult female who is 6 weeks pregnant. Which patient statement indicates that teaching has been effective? A) "I can drink on weekends only." B) "Smoking is bad for me and my baby." C) "Smoking is permitted as long as I do it outdoors." D) "Only one beer or one glass of wine is permitted while pregnant."

Ans: B Client Needs: Safe, Effective Care Environment: Management of Care Client Needs 2: Health Promotion and Maintenance Cognitive Level: Apply Feedback: Because almost all drugs are able to cross into the fetal circulation, it is important that a woman take no nonessential drugs, including alcohol and nicotine, during pregnancy. Alcohol perfuses across the placenta and can cause fetal alcohol sequence disorders. Because it is difficult to tell what quantity is "safe," pregnant women are advised to drink no alcohol during pregnancy. The statement that "smoking is bad for me and my baby" indicates that teaching has been effective. The patient should be instructed to avoid all alcohol intakes while pregnant and to not smoke.

The nurse is explaining the process of fertilization to a patient who has just learned of being pregnant. On which day during pregnancy should the nurse explain that the embryo implants on the uterine surface? A) Four days after fertilization B) Eight to 10 days after fertilization C) The 14th day of a "typical" menstrual cycle D) Ten days after the start of the menstrual flow

Ans: B Client Needs: Safe, Effective Care Environment: Management of Care Client Needs 2: Health Promotion and Maintenance Cognitive Level: Apply Page: 176 Feedback: Implantation, or contact between the growing structure and the uterine endometrium, occurs approximately 8 to 10 days after fertilization. Four days after fertilization the structure is a zygote. Implantation does not occur on the 14th day of a typical menstrual cycle or 10 days after the start of a menstrual flow.

A pregnant patient scheduled for an amniocentesis asks the nurse how the placenta is not punctured during the procedure. What should the nurse respond to the patient? A) "A uterus feels soft over the placenta site." B) "A sonogram to locate it will be done first." C) "It would not be harmful even if it were punctured." D) "Placentas always form on the posterior uterine wall."

Ans: B Client Needs: Safe, Effective Care Environment: Management of Care Client Needs 2: Physiological Integrity: Reduction of Risk Potential Cognitive Level: Apply Feedback: After the patient is placed in the supine position, a sonogram is done to determine the position of the fetus, the location of a pocket of amniotic fluid, and the placenta. The uterus does not feel soft over the placenta site. It would be harmful if the placenta were punctured during the procedure. Placentas do not always form on the posterior uterine wall.

The nurse determines that a fetal nonstress test is nonreactive for over 20 minutes. The nurse interprets this result as suggesting which situation? Select all that apply. A) The patient is sleeping. B) The patient is hypoglycemic. C) The patient is using an illicit drug. D) The patient is exercising too much. E) The patient is smoking while pregnant.

Ans: B, C, E Client Needs: Physiological Integrity: Reduction of Risk Potential Cognitive Level: Analyze Feedback: Reasons for lessened variability during a fetal nonstress test include maternal smoking, drug use, or hypoglycemia. Lessened variability does not occur because the patient is sleeping or because the patient is exercising too much.

The nurse is planning to instruct a patient who is 12 weeks pregnant on interventions to stop smoking. What should the nurse include in these instructions? Select all that apply. A) Purchase nicotine chewing gum. B) Follow a smoking cessation plan. C) Ask a friend to help with smoking cessation actions. D) Apply a nicotine patch when the cravings become severe. E) Ask the physician if a smoking cessation medication can be used.

Ans: B, C, E Client Needs: Safe, Effective Care Environment: Management of Care Client Needs 2: Health Promotion and Maintenance Cognitive Level: Apply Page: 189 Feedback: Interventions to help a pregnant patient with smoking cessation include following a smoking cessation plan, asking a friend to help with smoking cessation actions, and asking the physician if a smoking cessation medication can be used. The patient should not be instructed to purchase nicotine chewing gum or a patch because nicotine is a pregnancy category C drug, will cross into the placenta, and adversely affect the developing fetus.

. A pregnant woman is asked to observe fetal movements as a fetal assessment technique. The nurse would instruct her to: A) report if she feels no movement for any half-hour period. B) count only movements that are strong enough to hurt. C) count fetal movements for 1 hour at the same time each day. D) choose a different time frame each day to count movements.

Ans: C Client Needs: Health Promotion and Maintenance Cognitive Level: Understand Feedback: A healthy fetus moves at least 10 times daily. Counting fetal movements at the same time each day can help document fetal health.

An 18-year-old pregnant woman asks the nurse why she has to have a routine alpha-fetoprotein serum level drawn. The nurse explains that this: A) is a screening test for placental function. B) tests the ability of her heart to accommodate the pregnancy. C) may reveal chromosomal abnormalities. D) measures the fetal liver function.

Ans: C Client Needs: Health Promotion and Maintenance Cognitive Level: Understand Page: 181-182 Feedback: An alpha-fetoprotein analysis is a cost-effective screening test to detect chromosomal and open-body-cavity disorders.

A patient who is 28 weeks pregnant is demonstrating signs of placental insufficiency. The health care provider prescribes betamethasone. When teaching the patient about this drug's purpose, which information would the nurse include? A) It stops premature labor. B) It improves functioning of the placenta. C) It potentiates the formation of surfactant. D) It improves immunologic function of the fetus.

Ans: C Client Needs: Physiological Integrity: Pharmacological and Parenteral Therapies Cognitive Level: Apply Feedback: Synthetically increasing steroid levels in the fetus through the use of betamethasone can hurry alveolar maturation and surfactant production without interfering with permanent lung function prior to a preterm birth. Surfactant is formed and excreted by the alveolar cells of the lungs at about the 24th week of pregnancy, decreases alveolar surface tension on expiration, prevents alveolar collapse, and improves the infant's ability to maintain respirations in the outside environment at birth. Betamethasone is not being given to this patient to stop premature labor, improve the function of the placenta, or improve immunologic function of the fetus.

A patient who is 28 weeks pregnant is demonstrating signs of placental insufficiency. The health care provider prescribes betamethasone. When teaching the patient about this drug's purpose, which information would the nurse include? A) It stops premature labor. B) It improves functioning of the placenta. C) It potentiates the formation of surfactant. D) It improves immunologic function of the fetus.

Ans: C Client Needs: Physiological Integrity: Pharmacological and Parenteral Therapies Cognitive Level: Apply Page: 183 Feedback: Synthetically increasing steroid levels in the fetus through the use of betamethasone can hurry alveolar maturation and surfactant production without interfering with permanent lung function prior to a preterm birth. Surfactant is formed and excreted by the alveolar cells of the lungs at about the 24th week of pregnancy, decreases alveolar surface tension on expiration, prevents alveolar collapse, and improves the infant's ability to maintain respirations in the outside environment at birth. Betamethasone is not being given to this patient to stop premature labor, improve the function of the placenta, or improve immunologic function of the fetus.

A pregnant woman tends not to eat for long periods of time because of her busy work schedule. What process safeguards her fetus from becoming hypoglycemic during this time? A) The brain is too undeveloped to use glucose. B) Women naturally ingest complex carbohydrates to last for long periods during pregnancy. C) Somatomammotropin helps to regulate glucose levels. D) Fetal oxygen interferes with the metabolism of glucose and prolongs its action.

Ans: C Client Needs: Physiological Integrity: Physiological Adaptation Cognitive Level: Apply Feedback: Somatomammotropin makes insulin "less effective" than normal, thus decreasing its ability to produce hypoglycemia.

The nurse is teaching a patient in the first trimester of pregnancy about the importance of folic acid in the diet and how folic acid supplements might be beneficial. For which reason is the nurse teaching the patient about this vitamin? A) Maintains energy throughout the pregnancy B) Controls the risk of hypertension while pregnant C) Prevents neural tube disorders in the developing fetus D) Sustains a slow and steady weight gain while pregnant

Ans: C Client Needs: Safe, Effective Care Environment: Management of Care Client Needs 2: Health Promotion and Maintenance Cognitive Level: Analyze Page: 174 Feedback: Folic acid deficiency in pregnancy can lead to midline closure defects such neural tube disorders. One of the 2020 National Health Goals addresses an adequate folic acid intake while pregnant, and the nurse can help the nation achieve this goal by urging women to have an optimum folic acid level. Folic acid is not encouraged in the pregnant patient to maintain energy, control the risk of hypertension, or sustain a slow and steady weight gain while pregnant.

A pregnant patient asks why an a-fetoprotein serum level has been ordered. What should the nurse explain to the patient about this test? A) It screens for placenta function. B) It measures the fetal liver function. C) It may reveal chromosomal abnormalities. D) It tests the ability of the patient's heart to accommodate the pregnancy.

Ans: C Client Needs: Safe, Effective Care Environment: Management of Care Client Needs 2: Health Promotion and Maintenance Cognitive Level: Apply Feedback: a-Fetoprotein (AFP) is a substance produced by the fetal liver that can be found in both amniotic fluid and maternal serum. The level is abnormally high if the fetus has an open spinal or abdominal wall defect because the open defect allows more AFP to enter the mother's circulation. Although the reason is unclear, the level is low if the fetus has a chromosomal defect such as Down syndrome. Between 85% and 90% of neural tube anomalies, and 80% of Down syndrome babies can be detected by this method. The a-fetoprotein level is not used to screen for placenta functioning, measure fetal liver function, or test the ability of the patient's heart to accommodate the pregnancy.

The nurse is completing a physical assessment with a patient who has just learned of being pregnant. The patient's last menstrual period was August 15. When should the nurse instruct the patient that the baby will be due? A) July 15 B) June 22 C) May 22 D) April 15

Ans: C Client Needs: Safe, Effective Care Environment: Management of Care Client Needs 2: Health Promotion and Maintenance Cognitive Level: Apply Page: 187-188 Feedback: When using the Naegele rule, the nurse should count backward 3 calendar months from the first day of the patient's last menstrual period and then add 7 days. For August 15, the month would be May and the day would be 15 plus 7 or 22. May 22 is when the patient's baby is due. July 15, June 22, and April 15 are inappropriate applications of the Naegele rule.

A patient who learns of being 9 weeks pregnant asks the nurse to explain the changes that are occurring with her body. The woman states, "I'm really interested in learning what is happening so I can do the best for my baby." Which nursing diagnosis should the nurse identify as being appropriate for the patient at this time? A) Anxiety B) Impaired coping C) Deficient knowledge D) Readiness for enhanced knowledge

Ans: D Client Needs: Health Promotion and Maintenance Cognitive Level: Analyze Page: 174 Feedback: The patient asks the nurse to explain the changes that are occurring, which indicates that the patient is ready for more information or enhanced knowledge. Deficient knowledge would be appropriate if the patient where participating in some action or activity that would be harmful and would need information to correct that action. The patient's request for more information is not consistent with the diagnoses of anxiety or impaired coping.

A nurse is providing care to a woman early in her pregnancy. The woman is scheduled for a sonogram to confirm the presence of the gestational sac. Which instruction would the nurse include when teaching the woman about this test? A) "Do not to drink any fluid 1 hour prior to the study." B) "Be prepared for a catheter to be inserted prior to the study." C) "You'll need to empty your bladder just prior to the study. D) "Make sure to drink a large amount of fluid prior to the study."

Ans: D Client Needs: Health Promotion and Maintenance Cognitive Level: Apply Feedback: A full bladder before a sonogram helps to stabilize the uterus and best transmit the sound waves to the uterine cavity.

A nonstress test is an assessment test based on which phenomenon? A) Braxton-Hicks contractions cause fetal heart-rate alterations. B) Fetal heart rate slows in response to a uterine contraction. C) Fetal movement causes an increase in maternal heart rate. D) Fetal heart sounds increase in connection with fetal movement.

Ans: D Client Needs: Health Promotion and Maintenance Cognitive Level: Understand Feedback: Fetal heart rate increases about 15 beats per minute with fetal movement. Recording fetal movements is noninvasive monitoring, so it is termed a "nonstress" test.

A nurse is reviewing a journal article about fetal development and the formation of various body systems. When reading about the development of the digestive system, the nurse finds information related to the developmental abnormality of omphalocele. The nurse demonstrates understanding of this information by identifying which situation as the reason for an omphalocele? A) Fetus suffered a bowel obstruction at an early point in life. B) Fetal abdomen formed with a smaller internal cavity than normal. C) Intestines formed without sufficient nerve innervation for contraction. D) Intestines failed to return to the abdominal cavity during intrauterine life.

Ans: D Client Needs: Physiological Integrity: Physiological Adaptation Cognitive Level: Analyze Page: 183 Feedback: Because intestines grow more rapidly than the abdominal cavity, they are pushed into the base of the cord for a short span during intrauterine life. If for some reason they do not return to the abdominal cavity, an omphalocele will result.

The purpose of a circulatory shunt, such as the ductus arteriosus, is to: A) allow blood to bypass the fetal heart, which does not function as a pump until birth. B) allow fetal blood and maternal blood to mix freely. C) direct blood flow to the lungs to supply nutrients necessary for growth and maturation. D) permit oxygenated blood to supply the most important fetal organs.

Ans: D Client Needs: Physiological Integrity: Physiological Adaptation Cognitive Level: Understand Page: 184 Feedback: The ductus arteriosus helps propel oxygenated blood quickly to the coronary arteries, brain, and kidneys.

A pregnant patient is scheduled for an abdominal ultrasound. What should the nurse instruct the patient about this procedure? A) Avoid drinking fluid 1 hour prior to the procedure. B) Expect to have a catheter inserted prior to the procedure. C) Empty the bladder 1 hour and just prior to the start of the procedure. D) Drink a glass of water every 15 minutes starting 90 minutes before the procedure.

Ans: D Client Needs: Safe, Effective Care Environment: Management of Care Client Needs 2: Health Promotion and Maintenance Cognitive Level: Apply Feedback: The sound waves reflect best if the uterus can be held stable so it is helpful if the woman has a full bladder at the time of the procedure. To ensure this, ask her to drink a full glass of water every 15 minutes beginning 90 minutes before the procedure and not void until after the procedure. The patient will not have a catheter inserted for this procedure. The patient should not avoid fluids 1 hour prior to the procedure. The bladder should not be emptied until the procedure concludes.

A pregnant patient is concerned that the baby is going to drown in the uterus because of the fluid. What should the nurse respond about fetal respiration? A) "You are breathing for the baby." B) "The baby's breathing is very minor until delivery." C) "The baby's lungs can accommodate all of the fluid." D) "Oxygen is provided to the baby through the placenta."

Ans: D Client Needs: Safe, Effective Care Environment: Management of Care Client Needs 2: Health Promotion and Maintenance Cognitive Level: Apply Page: 177 Feedback: Fetal circulation differs from extrauterine circulation because the fetus derives oxygen and excretes carbon dioxide not from gas exchange in the lung but from exchange in the placenta. The baby's lungs are not functioning in utero so the response that the baby's breathing is very minor until delivery and the baby's lungs being able to accommodate the fluid are incorrect. The patient is not "breathing for the baby."

Nursing Care Planning Based on 2020 National Health Goals

Folic acid deficiency in pregnancy can lead to midline closure defects such as neural tube disorders. Nurses can help the nation achieve these goals by urging women to plan their pregnancies so they can enter the pregnancy in good health and with an optimum folic acid level. Educating women about the importance of attending prenatal care is another important role.

DETERMINATION OF ESTIMATED BIRTH DATE

It is impossible to predict with a high degree of accuracy the exact day an infant will be born because fewer than 5% of pregnancies end exactly 280 days from the last menstrual period; fewer than half end within 1 week of the 280th day. Traditionally, this date was referred to as the estimated date of confinement (EDC). Because women are no longer "confined" after childbirth, the acronym EDB (estimated date of birth) is more commonly used today

umbilical cord functions

Its function is to transport oxygen and nutrients to the fetus from the placenta and to return waste products from the fetus to the placenta. It is about 53 cm (21 in.) in length at term and about 2 cm (0.75 in.) thick. The bulk of the cord is a gelatinous mucopolysaccharide called Wharton jelly, which gives the cord body and prevents pressure on the vein and arteries that pass through it.

INTEGUMENTARY SYSTEM

The skin of a fetus appears thin and almost translucent until subcutaneous fat begins to be deposited underneath it at about 36 weeks. Skin is covered by soft downy hairs (lanugo) that serve as insulation to preserve warmth in utero as well as a cream cheese-like substance, vernix caseosa, which is important for lubrication and for keeping the skin from macerating in utero. Both lanugo and vernix are still present at birth.

The Nursing Role and Nursing Care During Normal Pregnancy and Birth Attending to the psychological and physiologic changes of pregnancy assures the health of the mother, and a healthy mother is a positive predictor for a healthy baby.

You can foster a healthy outcome by obtaining a complete history and providing a physical examination that focuses on those components that influence fetal development. Vital signs are monitored following a recommended interval during pregnancy. Prenatal visits include standard guidelines, which may be altered if a pregnancy is at risk due to complications.

STEM CELLS During the first 4 days of life, zygote cells are termed totipotent stem cells, or cells so undifferentiated they have the potential to grow into

any cell in the human body. In another 4 days, as the structure implants and becomes an embryo, cells begin to show differentiation or lose their ability to become any body cell. Instead, they are slated to become specific body cells, such as nerve, brain, or skin cells, and are termed pluripotent stem cells. In yet another few days, the cells grow so specific they are termed multipotent, or are so specific they cannot be deterred from growing into a particular body organ such as spleen or liver or brain

EVIDENCE-BASED PRACTICE To investigate whether there are any psychosocial predictors of women who smoke during pregnancy, a cross-sectional analysis of a birth cohort was reviewed. In this prospective study, the answers to questionnaires completed by 514 mothers shortly after the birth of their full-term infants found that 14.8% of the participants smoked. Of those women responded that they smoked during pregnancy, they were also more likely to have the following characteristics: lower education, maternal age less than 20 years, unmarried, history of elective abortion, history of unplanned pregnancy, lack of emotional acceptance of the pregnancy by the mother and father, emotional distress, and alcohol consumption Based on the previous study, which statement by Liz Calhorn would make the nurse most worried she might have difficulty quitting smoking during the remainder of her pregnancy? a. "I sometimes do have a few beers on the weekend with my boyfriend." b. "When I feel tense, I like to shop. It really takes away that bad feeling." c. "I'm trying to stop smoking so I won't have to smoke around my baby." d. "My mother had five children with no trouble; why am I so different?"

a. "I sometimes do have a few beers on the weekend with my boyfriend."

INFORMATICS Liz Calhorn asks the nurse why her nurse midwife is concerned whether her fetus's lungs are producing surfactant. The nurse's best answer would be: a. "Surfactant keeps lungs from collapsing at birth, so it aids newborn breathing." b. "Surfactant is produced by the fetal liver, so its presence reveals liver maturity." c. "Surfactant is necessary for antibody production, so it helps prevents infection." d. "Surfactant reveals mature kidney function, as it is important for fetal

a. "Surfactant keeps lungs from collapsing at birth, so it aids newborn breathing."

Liz Calhorn is scheduled to have an amniocentesis to test for fetal maturity. To help make sure the procedure is successful, what instruction would be best to give her before this procedure? a. "Void (pee) immediately before the procedure to reduce the size of your bladder." b. "The X-ray used to reveal your fetus's position will have no long-term fetal effects." c. "The IV fluid used to dilate your uterus is isotonic saline so will not hurt the fetus." d. "Your fetus will have less amniotic fluid for the rest of pregnancy, but that's all right."

a. "Void (pee) immediately before the procedure to reduce the size of your bladder."

For an ultrasound, intermittent sound waves of high frequency (above the audible range) are projected toward the uterus by a transducer placed on the

abdomen or in the vagina. The sound frequencies that bounce back from the fetus can be displayed on an oscilloscope screen as a visual image. The frequencies returning from tissues of various thicknesses and properties present distinct appearances. A permanent record can be made of the scan for the woman's electronic health record; a copy of the scan can be offered to her as a baby book souvenir. -Images are so clear that the fetal heart as well as movement of the extremities, such as bringing a hand to the mouth to suck a thumb, can be seen. A parent who is in doubt her fetus is well or whole can be greatly reassured by viewing such a sonogram image.

MILESTONES OF FETAL GROWTH AND DEVELOPMENT When fetal milestones occur can be confusing because the life of the fetus is typically measured from the time of ovulation or fertilization (ovulation age), but the length of a pregnancy is more commonly measured from the first day of the last menstrual period (gestational age). Because ovulation and fertilization take place about 2 weeks after the last menstrual period, the ovulation age of the fetus is

always 2 weeks less than the length of the pregnancy or the gestational age Both ovulation and gestational age are typically reported in lunar months (4-week periods) or in trimesters (3-month periods) rather than in weeks. In lunar months, a total pregnancy is 10 months (40 weeks or 280 days) long; a fetus grows in utero for 9.5 lunar months or three full trimesters (38 weeks or 266 days).

IMMUNE SYSTEM Immunoglobulin (Ig) G maternal antibodies cross the placenta into the fetus as early as the 20th week and certainly by the 24th week of intrauterine life to give a fetus temporary passive immunity against

diseases for which the mother has antibodies. These often include poliomyelitis, rubella (German measles), rubeola (regular measles), diphtheria, tetanus, infectious parotitis (mumps), hepatitis B, and pertussis (whooping cough). Infants born before this antibody transfer has taken place have no natural immunity and so need more than the usual protection against infectious disease in the newborn period.

The amniotic membrane is a

dual-walled sac with the chorion as the outmost part and the amnion as the innermost part. The two fuse together as the pregnancy progresses, and by term, they appear to be a single sac. They have no nerve supply, so when they spontaneously rupture at term (a pregnant woman's "water breaks") or are artificially ruptured via a procedure, neither the pregnant woman nor fetus experiences any pain

OUTCOME IDENTIFICATION AND PLANNING Plans for care should include ways to :

educate potential parents about teratogens (i.e., any substance harmful to a fetus) that have the potential to interfere with fetal health. Outcome criteria established for teaching about fetal growth should be realistic and based on the parents' previous knowledge and desire for information. When additional assessment measures are necessary, such as an amniocentesis or an ultrasound examination, add this information to the teaching plan, explaining why further assessment is necessary and what the parents can expect from the procedure.

Almost immediately, the blastocyst burrows deeply into the endometrium and establishes an effective communication network with the blood system of the endometrium. Once implanted, the zygote is called an

embryo

The fetus of a woman with diabetes may develop a larger than usual placenta from

excess fluid collected between cells.

Newborns need careful assessment at birth for

hypoglycemia (low blood sugar) and hyperbilirubinemia (excessive breakdown products from destroyed red blood cells), two serious problems that can occur in the first 24 hours after birth because, although active, liver function is still immature.

A fetus only becomes capable of active antibody production late in pregnancy. Generally, it is not necessary for a fetus to produce antibodies because they need to be manufactured only to counteract an invading antigen, and antigens rarely invade the intrauterine space. Because IgA and IgM antibodies (the types which develop to actively counteract infection) cannot cross the placenta, their presence in a newborn is proof that the fetus has been exposed to an ?

infection.

Braxton Hicks contractions, the barely noticeable uterine contractions present from about the 12th week of pregnancy on, aid in maintaining pressure in the

intervillous spaces by closing off the uterine veins momentarily with each contraction.

Placental circulation As early as the 12th day of pregnancy, maternal blood begins to collect in the

intervillous spaces of the uterine endometrium surrounding the chorionic villi. By the third week, oxygen and other nutrients such as glucose, amino acids, fatty acids, minerals, vitamins, and water osmose from the maternal blood through the cell layers of the chorionic villi into the villi capillaries. From there, nutrients are transported to the developing embryo.

The gastrointestinal tract is sterile before birth. Because vitamin K, necessary for blood clotting, is synthesized by the action of bacteria in the intestines, vitamin K levels are almost nonexistent in a fetus and are still low in a newborn ,vitamin K is routinely administered

intramuscularly at birth Sucking and swallowing reflexes are not mature until the fetus is approximately 32 weeks gestation, or weighs 1,500 g. However, strong suck and swallowing reflexes may not be present until the fetus is full term.

CARDIOVASCULAR SYSTEM The cardiovascular system is one of the first systems to become functional in

intrauterine life. Simple blood cells joined to the walls of the yolk sac progress to become a network of blood vessels and a single heart tube, which forms as early as the 16th day of life and beats as early as the 24th day. The septum that divides the heart into chambers develops during the sixth or seventh week; heart valves develop in the seventh week. The heartbeat may be heard with a Doppler instrument as early as the 10th to 12th week of pregnancy. An electrocardiogram (ECG) may be recorded on a fetus as early as the 11th week, although early ECGs are not accurate until conduction is more regulated at about the 20th week of pregnancy.

NERVOUS SYSTEM Like the circulatory system, the nervous system begins to develop extremely early in pregnancy:

• A neural plate (a thickened portion of the ectoderm) is apparent by the third week of gestation. The top portion differentiates into the neural tube, which will form the central nervous system (brain and spinal cord), and the neural crest, which will develop into the peripheral nervous system. • All parts of the brain (cerebrum, cerebellum, pons, and medulla oblongata) form in utero, although none are completely mature at birth. Brain growth continues at high levels until 5 or 6 years of age. • Brain waves can be detected on an electroencephalogram (EEG) by the eighth week. • The eye and inner ear develop as projections of the original neural tube. • By 24 weeks, the ear is capable of responding to sound, and the eyes exhibit a pupillary reaction, indicating sight is present.

Biophysical profiles may be done as often as daily during a high-risk pregnancy. The fetal scores are as follows:

• A score of 8 to 10 means the fetus is considered to be doing well. • A score of 6 is considered suspicious. • A score of 4 denotes a fetus potentially in jeopardy -For simplicity, some centers use only two assessments (amniotic fluid index [AFI] and a nonstress test) for the analysis. Referred to as a modified biophysical profile, this predicts short-term viability by the nonstress test and long-term viability by the AFI. A healthy fetus should show a reactive nonstress test and an AFI range between 5 and 25 cm

Amniotic fluid-obtained through amniocentesis can be analyzed for:

• AFP • Acetylcholinesterase, another compound that rises to high levels if a neural tube anomaly is present • Bilirubin determination. The presence of bilirubin may be analyzed if a blood incompatibility is suspected. If bilirubin is going to be analyzed, the specimen must be free of blood or a false-positive reading will occur. • Chromosome analysis. A few fetal skin cells are always present in amniotic fluid so these cells may be cultured and stained for karyotyping for genetic analysis. • Inborn errors of metabolism. A number of inherited diseases that are caused by inborn errors of metabolism can be detected by amniocentesis. For a condition to be identified, an errant enzyme must be present in the amniotic fluid as early as the time of the procedure. Examples of illnesses that can be detected in this way are sickle cell disease, cystic fibrosis, muscular dystrophy, Tay-Sachs disease, and maple syrup urine disease (an amino acid disorder). • L/S ratio. Lecithin and sphingomyelin are the protein components of the lung enzyme surfactant that the alveoli begin to form at the 22nd to 24th weeks of pregnancy. Following an amniocentesis, the L/S ratio may be determined quickly by a shake test (if bubbles appear in the amniotic fluid after shaking, the ratio is mature), but the specimen is then sent for laboratory analysis for a definite analysis. An L/S ratio of 2:1 is traditionally accepted as lung maturity. Infants of mothers with severe diabetes may have false-mature readings of lecithin because stress to the infant in utero tends to mature lecithin pathways early. This means fetal values must be considered in light of the presence of maternal diabetes or the infants may be born with mature lung function but be immature overall (a fragile giant), causing them to not do well in postnatal life

Because the average fetus moves about twice every 10 minutes, and movement causes the heart rate to increase, there will typically be two or more instances of fetal heart rate acceleration in a 20-minute rhythm strip. Variability is rated as:

• Absent: No peak-to-trough range is detectable. • Minimal: An amplitude range is detectable but the rate is 5 beats/min or fewer. • Moderate or normal: An amplitude range is detectable; rate is 6 to 25 beats/min. • Marked: An amplitude range is detectable; rate is greater than 25 beats/min

If a photograph is taken through the fetoscope, it can document a problem or reassure parents that their infant is perfectly formed. The main reasons the procedure is used are to:

• Confirm the intactness of the spinal column. • Obtain biopsy samples of fetal tissue and fetal blood samples. • Determine meconium staining is not present. • Perform elemental surgery, such as inserting a polyethylene shunt into the fetal ventricles to relieve hydrocephalus or anteriorly into the fetal bladder to relieve a stenosed urethra. -It may be possible to repair a neural tube defect such as meningocele or improve the outcome of myelomeningocele by fetoscopy

Ultrasonography Ultrasonography, which measures the response of sound waves against solid objects, is a much-used tool for fetal health assessments. It can be used to:

• Diagnose pregnancy as early as 6 weeks gestation. • Confirm the presence, size, and location of the placenta and amniotic fluid. • Establish a fetus is growing and has no gross anomalies such as hydrocephalus; anencephaly; or spinal cord, heart, kidney, and bladder concerns. • Establish the sex if a penis is revealed. • Establish the presentation and position of the fetus. • Predict gestational age by measurement of the biparietal diameter of the head or crown-to-rump measurement. • Discover complications of pregnancy, such as the presence of an intrauterine device, hydramnios (excessive amniotic fluid) or oligohydramnios (lessened amniotic fluid), ectopic pregnancy, missed miscarriage, abdominal pregnancy, placenta previa (a low-implanted placenta), premature separation of the placenta, coexisting uterine tumors, or multiple pregnancy. Genetic disorders such as Down syndrome and fetal anomalies such as neural tube disorders, diaphragmatic hernia, or urethral stenosis also can be diagnosed. Fetal death can be revealed by a lack of heartbeat and respiratory movement. • After birth, a sonogram may be used to detect a retained placenta or poor uterine involution in the new mother

Daily Fetal Movement Count (Kick Counts) Fetal movement that can be felt by the mother (quickening) occurs at approximately 18 to 20 weeks of pregnancy and peaks in intensity at 28 to 38 weeks. After that time, a healthy fetus moves with a degree of consistency at about 10 times per hour. In contrast, a fetus who is not receiving enough nutrients because of poor maternal nutrition or placental insufficiency has greatly decreased movements. The technique for "kick counts" varies from institution to institution, but a typical method used is to ask women with high-risk pregnancies to:

• Lie in a left recumbent position after a meal. • Observe and record the number of fetal movements (kicks) their fetus makes until they have counted 10 movements. • Record the time (typically, this is under an hour). • If an hour passes without 10 movements, they should walk around a little and try a count again. • If 10 movements (kicks) cannot be felt in a second 1-hour period, they should telephone their primary healthcare provider. The fetus could be healthy but sleeping during this time, so lack of typical movements may not be serious, but it is an indication for further assessment