OB Chapter 13- Book

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levels of hCG as low as _____ can be detected as early as the first day of a missed menstrual period

pyrosis

"heartburn" "acid indigestion" Increased progesterone production causes decreased tone and motility of smooth muscles, resulting in esophageal regur- gitation, slower emptying time of the stomach, and reverse peristalsis.

Striae gravidarum

"stretch marks" which appear in 50% to 90% of pregnant women during the second half of pregnancy, may be caused by action of adrenocorticosteroids. Striae reflect separation within the underlying connective (collagen) tissue of the skin. These slightly depressed streaks tend to occur over areas of maximal stretch (i.e., abdomen, thighs, and breasts). The stretching sometimes causes a sensation that resembles itching. The ten- dency to develop striae may be familial. After birth they usually fade, although they never disappear completely. Color of striae varies depending on the pregnant woman's skin color. The striae appear pinkish on a woman with light skin and are lighter than surrounding skin in dark-skinned women. In the multip- ara, in addition to the striae of the present pregnancy, glisten- ing silvery lines (in light-skinned women) or purplish lines (in dark-skinned women) are commonly seen. These represent the scars of striae from previous pregnancies.

angiomas

"vascular spiders" They are tiny, star-shaped or branched, slightly raised and pulsating end-arterioles usually found on the neck, thorax, face, and arms. They occur as a result of elevated levels of circulating estrogen. The spiders are bluish in color and do not blanch with pressure. Vascular spiders appear during the second to the fifth month of pregnancy in almost 65% of Caucasian women and 10% of African-American women. The spiders usually disappear after birth

ptyalism

(excessive salivation), which may be caused by the decrease in unconscious swallowing by the woman when nau- seated or from stimulation of salivary glands by eating starch

GTPAL

(gravidity, term, preterm, abortions, living children)

presumptive signs of pregnancy:

3-4 wk Breast changes 4 wk Amenorrhea 4-14 wk Nausea, vomiting 6-12 wk Urinary frequency 12 wk Fatigue 16-20 wk Quickening

Cardiovascular system changes occur during pregnancy. Which finding would be considered normal for a woman in her second trimester?

Increased pulse rate Between 14 and 20 weeks of gestation, the pulse increases about 10 to 15 beats/min, which persists to term.

Chadwick sign (blue cervix)

Increased vascularity results in a violet-bluish vaginal mucosa and cervix. The deepened color, termed the_______, may be evident as early as the sixth week but is easily noted at the eighth week of pregnancy

A woman is 6 weeks pregnant. She has had a previous spontaneous abortion at 14 weeks of gestation and a pregnancy that ended at 38 weeks with the birth of a stillborn girl. What is her gravidity and parity according to the GTPAL system?

3-1-0-1-0 According to the GPTAL system, this woman's gravidity and parity information is calculated as follows:G: Total number of times the woman has been pregnant (she is pregnant for the third time) T: Number of pregnancies carried to term (only one pregnancy resulted in a fetus at term)P: Number of pregnancies that resulted in a preterm birth (none)A: Abortions or miscarriages before the period of viability (she has had one)L: Number of children born who are currently living (she has no living children)3-1-0-1-0 is the correct calculation of this woman's gravidity and parity.

Which hematocrit (HCT) and hemoglobin (HGB) results represent the lowest acceptable values for a woman in the third trimester of pregnancy?

33% HCT; 11 g/dL HGB

probable signs of pregnancy:

5 wk Goodell sign 6-8 wk Chadwick sign 6-12 wk Hegar sign 4-12 wk Positive result of pregnancy test (serum) 6-12 wk Positive result of pregnancy test (urine) 16 wkBraxton Hicks contractions 16-28 wk Ballottement

positive signs of pregnancy

5-6 wk Visualization of fetus by real-time ultrasound examination 6 wk Fetal heart tones detected by ultrasound examination 16 wk Visualization of fetus by radiographic study 8-17 wkFetal heart tones detected by Doppler ultrasound stethoscope 17-19 wk Fetal heart tones detected by fetal stethoscope 19-22 wk Fetal movements palpated Late pregnancy: Fetal movements visible

Goddells sign

A softening of the cervical tip called ____ can be observed at approximately the beginning of the sixth week in a normal, unscarred cervix. This sign is brought about by increased vascularity, slight hypertrophy, and hyperplasia (increase in number of cells) of the muscle and its collagen-rich connective tissue, which becomes loose, edematous, highly elastic, and increased in volume. The glands near the external os proliferate beneath the stratified squamous epi- thelium, giving the cervix the velvety appearance characteristic of pregnancy.

precolostrum

A thin, clear, viscous secretory material that can be found in the acini cells by the third month of gestation.

integumentary system changes during pregnancy

Alterations in hormonal balance and mechanical stretching are responsible for several changes in the integumentary sys- tem during pregnancy. Hyperpigmentation is stimulated by the anterior pituitary hormone melanotropin, which is increased during pregnancy. Darkening of the nipples, the areolae, the axillae, and the vulva occurs about the sixteenth week of gestation. Nail growth may be accelerated. Some women may notice thinning and softening of the nails. Oily skin and acne vulgarismay occur during pregnancy. For some women, the skin clears and looks radiant. Hirsutism, the excessive growth of hair or growth of hair in unusual places, is commonly reported. An increase in fine hair growth may occur but tends to disappear after pregnancy; however, growth of coarse or bristly hair does not usually disappear. The rate of scalp hair loss slows during pregnancy, while increased hair loss may be noted in the post- partum period. Increased blood supply to the skin leads to increased per- spiration. Women feel hotter during pregnancy, a condition possibly related to a progesterone-induced increase in body temperature and the increased BMR.

blood pressure changes during pregnancy

Arterial blood pressure (brachial artery) is affected by age, activity level, presence of health problems, and circadian rhythm. Other factors include use of alcohol, smok- ing, and pain. Additional factors must be considered during pregnancy. These factors include maternal anxiety, maternal position, and size and type of blood pressure apparatus. Maternal anxiety can elevate readings. If an elevated reading is found, the woman is given time to rest, and the reading is repeated. Maternal position affects readings. Brachial blood pressure is higher when the woman is sitting than when she is lying in the lateral recumbent position. The position of the arm can also make a difference in the measurement. If the arm is above the heart, the reading will be lower than the accurate reading; if held below the heart, the reading will be higher. Therefore at each prenatal visit the reading should be obtained in the same arm and with the woman in the same position with her back and arm supported and with her upper arm at the level of the right atrium. Systolic blood pressure usually remains the same as the pre- pregnancy level but may decrease slightly as pregnancy advances. Diastolic blood pressure begins to decrease in the first trimester, continues to drop until 24 to 32 weeks, then gradually increases and returns to prepregnancy levels by term

Hegar sign

At approximately 6 weeks of gestation, softening and compressibility of the lower uterine segment (the uterine isthmus) occur This results in exaggerated uterine anteflexion during the first 3 months of pregnancy. In this position the uterine fundus presses on the urinary bladder, causing the woman to have urinary frequency.

lightening

Between weeks 38 and 40, fundal height drops as the fetus begins to descend and engage in the pelvis

acid base balance during pregnancy

By about the tenth week of pregnancy, there is a decrease of about 5 mm Hg in the partial pressure of carbon dioxide (Pco2). Progesterone may be responsible for increasing the sensitivity of the respiratory center receptors, so that tidal volume is increased, Pco2 decreases, the base excess (HCO3 or bicarbonate) decreases, and pH increases slightly. These alterations in acid-base balance indicate that preg- nancy is a state of compensatory respiratory alkalosis (Gor- don, 2007). These changes also facilitate the transport of CO2 from the fetus and O2 release from the mother to the fetus

Mean Arterial Pressure (MAP) during pregnancy

Calculating the mean arterial pressure (MAP) (mean of the blood pressure in the arterial circulation) can increase the diag- nostic value of the findings. Normal MAP readings in the non- pregnant woman are 86.4 mm Hg ± 7.5 mm Hg. MAP readings for a pregnant woman are slightly higher

cardiac output during pregnancy

Cardiac output increases from 30% to 50% over the nonpregnant rate by the thirty-second week of preg- nancy; it declines to about a 20% increase at 40 weeks of ges- tation. This elevated cardiac output is caused by an increase in stroke volume and heart rate and occurs in response to increased tissue demands for oxygen (Monga, 2009). Cardiac output in late pregnancy is appreciably higher when the woman is in the lateral recumbent position than when she is supine. In the supine position the large, heavy uterus often impedes venous return to the heart and affects blood pressure. Cardiac output increases with any exertion, such as labor and birth. Table 13-4 summarizes cardiovascular changes in pregnancy.

anatomic changes in the renal system during pregnancy

Changes in renal structure during preg- nancy result from hormonal activity (estrogen and progester- one), pressure from an enlarging uterus, and an increase in blood volume. As early as the tenth week of pregnancy, the renal pelves and the ureters dilate. Dilation of the ureters is more pronounced above the pelvic brim, in part because they are compressed between the uterus and the pelvic brim. In most women, the ureters below the pelvic brim are of normal size. The smooth-muscle walls of the ureters undergo hyperplasia, hypertrophy, and muscle tone relaxation. The ureters elongate, become tortuous, and form single or double curves. In the latter part of pregnancy, the renal pelvis and ureter are dilated more on the right side than on the left because the heavy uterus is displaced to the right by the sigmoid colon. Because of these changes, a larger volume of urine is held in the pelves and ureters, and urine flow rate is slowed. The result- ing urinary stasis or stagnation has the following consequences: • A lag occurs between the time urine is formed and when it reaches the bladder. Therefore clearance test results may reflect substances contained in glomerular filtrate several hours before. • Stagnated urine is an excellent medium for the growth of microorganisms. In addition, the urine of pregnant women contains more nutrients, including glucose, thereby increas- ing the pH (making the urine more alkaline). This makes pregnant women more susceptible to urinary tract infection. Bladder irritability, nocturia, and urinary frequency and urgency (without dysuria) are commonly reported in early pregnancy. Near term, bladder symptoms may return, espe- cially after lightening occurs. Urinary frequency results initially from increased bladder sensitivity and later from compression of the bladder (see Fig. 13-8). In the second trimester, the bladder is pulled up out of the true pelvis into the abdomen. The urethra lengthens to 7.5 cm as the bladder is displaced upward. The pelvic congestion that occurs in pregnancy is reflected in hyperemia of the blad- der and urethra. This increased vascularity causes the blad- der mucosa to be traumatized and bleed easily. Bladder tone may decrease, which increases the bladder capacity to 1500 ml. At the same time, the bladder is compressed by the enlarging uterus, resulting in the urge to void even if the bladder contains only a small amount of urine.

venous changes in legs during pregnancy

Compression of the iliac veins and inferior vena cava by the uterus causes increased venous pressure and reduced blood flow in the legs (except when the woman is in the lateral position). These alterations contribute to the dependent edema, varicose veins in the legs and vulva, and hemorrhoids that develop in the latter part of term pregnancy

pH of vagina during pregnancy

During pregnancy the pH of vaginal secretions is more acidic than normal (ranging from approximately 3.5 to 6 [normal 4 to 5]) because of increased production of lactic acid. Although this acidic environment provides more protection from some organisms, the pregnant woman is more vulnerable to other infections, especially yeast infections because the glycogen-rich environment is more susceptible to Candida albicans

thyroid gland during pregnancy

During pregnancy, gland activity and hor- mone production increase. The increased activity is reflected in a moderate enlargement of the thyroid gland caused by hyperplasia of the glandular tissue and increased vascularity (Cunningham et al., 2010). Thyroxine-binding globulin (TBG) increases as a result of increased estrogen levels. This increase begins at about 20 weeks of gestation. The level of total (free and bound) thyroxine (T4) increases between 6 and 9 weeks of gestation and plateaus at 18 weeks of gestation. Free thyroxine (T4) and free triiodothyronine (T3) return to nonpregnant lev- els after the first trimester. Despite these changes in hormone production, hyperthyroidism usually does not develop in the pregnant woman.

Pituitary and placental hormones

During pregnancy, the elevated levels of estrogen and progesterone (produced first by the corpus luteum in the ovary until about 14 weeks of gesta- tion and then by the placenta) suppress secretion of follicle- stimulating hormone (FSH) and luteinizing hormone (LH) by the anterior pituitary. The maturation of a follicle and ovu- lation do not occur. Although the majority of women have amenorrhea (absence of menses), at least 20% have some slight, painless spotting during early gestation. Implantation bleeding and bleeding after intercourse related to cervical friability can occur. Most of the women experiencing slight gestational bleed- ing continue to term and have normal infants; however, all instances of bleeding should be reported and evaluated. After implantation, the fertilized ovum and the chorionic villi produce hCG, which maintains the production by the cor- pus luteum of estrogen and progesterone until the placenta takes over production

appetite during pregnancy

During pregnancy, the woman's appetite and food intake fluctuate. Early in pregnancy, some women have nau- sea with or without vomiting (morning sickness), possibly in response to increasing levels of hCG and altered carbohydrate metabolism (Gordon, 2007). Morning sickness or nausea and vomiting of pregnancy (NVP) appears at about 4 to 6 weeks of gestation and usually subsides by the end of the third month (first trimester) of pregnancy (see Chapter 15). Severity var- ies from mild distaste for certain foods to more severe vom- iting. The condition may be triggered by the sight or odor of various foods. By the end of the second trimester, the appetite increases in response to increasing metabolic needs. Rarely does NVP have harmful effects on the embryo, fetus, or the woman. Whenever the vomiting is severe or persists beyond the first trimester, or when it is accompanied by fever, pain, or weight loss, further evaluation is necessary, and medical intervention is likely (see Chapter 29). Women also may have changes in their sense of taste, leading to cravings and changes in dietary intake. Some women have nonfood cravings (called pica), such as for ice, clay, and laun- dry starch. Usually the subjects of these cravings, if consumed in moderation, are not harmful to the pregnancy if the woman has adequate nutrition with appropriate weight gain (Gordon, 2007). See Chapter 14 for a discussion of nutrition in pregnancy.

mammary glands during pregnancy

During the second and third trimesters, growth of the mam- mary glands accounts for the progressive breast enlargement. The high levels of luteal and placental hormones in pregnancy promote proliferation of the lactiferous ducts and lobule- alveolar tissue, so that palpation of the breasts reveals a general- ized, coarse nodularity. Glandular tissue displaces connective tissue, and as a result, the tissue becomes softer and looser. Although development of the mammary glands is func- tionally complete by midpregnancy, lactation is inhibited until a decrease in estrogen level occurs after the birth.

Over-the-counter (OTC) pregnancy tests usually rely on which technology to test for human chorionic gonadotropin (hCG)?

Enzyme-linked immunosorbent assay (ELISA) OTC pregnancy tests use ELISA for its one-step, accurate results.

A nurse teaches a pregnant woman about the presumptive, probable, and positive signs of pregnancy. The woman demonstrates understanding of the nurse's instructions if she states that a positive sign of pregnancy is:

Fetal movement palpated by the nurse-midwife. Positive signs of pregnancy are those that are attributed to the presence of a fetus, such as hearing the fetal heartbeat and palpating fetal movement.

breast changes during pregnancy

Fullness, heightened sensitivity, tingling, and heaviness of the breasts occur in the early weeks of gestation in response to increased levels of estrogen and progesterone. Breast sensitivity varies from mild tingling to sharp pain. Nipples and areolae become more pigmented, secondary pinkish areolae develop, extending beyond the primary areolae, and nipples become more erectile.

Which presumptive sign (felt by woman) or probable sign (observed by the examiner) of pregnancy is not matched with another possible cause(s)?

Goodell sign—cervical polyps Goodell sign might be the result of pelvic congestion,

During a client's physical examination, the nurse notes that the lower uterine segment is soft on palpation. The nurse would document this finding as:

Hegar sign. At approximately 6 weeks of gestation, softening and compressibility of the lower uterine segment occur; this is called the Hegar sign.

Esophagus, Stomach, and Intestines during pregnancy

Herniation of the upper portion of the stomach (hiatal hernia) occurs after the seventh or eighth month of pregnancy in about 15% to 20% of pregnant women. This condition results from upward displace- ment of the stomach, which causes the hiatus of the diaphragm to widen. It occurs more often in multiparas and older or obese women. Increased estrogen production causes decreased secretion of hydrochloric acid; therefore peptic ulcer formation or flare-up of existing peptic ulcers is uncommon during pregnancy and symptoms may improve Iron is absorbed more readily in the small intestine in response to increased needs during pregnancy. Even when the woman is deficient in iron, it will continue to be absorbed in suf- ficient amounts for the fetus to have a normal hemoglobin level. Increased progesterone (causing loss of muscle tone and decreased peristalsis) results in an increase in water absorption from the colon and may cause constipation. Constipation also may result from hypoperistalsis (sluggishness of the bowel), food choices, lack of fluids, iron supplementation, decreased activity level, abdominal distention by the pregnant uterus, and displacement and compression of the intestines. If the pregnant woman has hemorrhoids (see Fig. 13-10) and is constipated, the hemorrhoids may become everted or may bleed during strain- ing at stool.

Montgomery tubercles

Hypertrophy of the sebaceous (oil) glands embedded in the primary areolae, may be seen around the nipples These sebaceous glands may have a protective role in that they keep the nipples lubricated for breastfeeding.

functional changes in the renal system during pregnancy

In normal pregnancy, renal function is altered considerably. Glomerular filtration rate (GFR) and renal plasma flow (RPF) increase early in pregnancy (Monga, 2009). These changes are caused by pregnancy hormones, an increase in blood volume, the woman's posture, physical activity, and nutritional intake. The woman's kidneys must manage the increased metabolic and circulatory demands of the maternal body and the excretion of fetal waste products. Renal function is most efficient when the woman lies in the lateral recumbent position and least efficient when the woman assumes a supine position. A side-lying position increases renal perfusion, which increases urinary output and decreases edema. When the pregnant woman is lying supine, the heavy uterus compresses the vena cava and the aorta, and cardiac output decreases. As a result, blood flow to the brain and heart is continued at the expense of other organs, including the kid- neys and uterus.

abdominal discomfort during pregnancy

Intraabdominal alterations that can cause discomfort include pelvic heaviness or pressure, round ligament tension, flatulence, distention and bowel cramping, and uterine contractions. In addition to displacement of intes- tines, pressure from the expanding uterus causes an increase in venous pressure in the pelvic organs. Although most abdominal discomfort is a consequence of normal maternal alterations, the health care provider must be constantly alert to the possibility of disorders such as bowel obstruction or an inflammatory process. Appendicitis may be difficult to diagnose in pregnancy because the appendix is displaced upward and laterally, high and to the right, away from McBurney's point

false-positive and false-negative pregnancy test results

It is important to know if the woman is a substance abuser and what medications she is taking, because medications such as anticonvulsants and tranquilizers can cause false-positive results, whereas diuretics and promethazine can cause false-negative results Improper collection of the specimen, hormone- producing tumors, and laboratory errors also can cause false results.

changes in the neurologic system during pregnancy

Little is known regarding specific alterations in function of the neurologic system during pregnancy, aside from hypotha- lamic-pituitary neurohormonal changes. Specific physiologic alterations resulting from pregnancy may cause the following neurologic or neuromuscular symptoms: • Compression of pelvic nerves or vascular stasis caused by enlargement of the uterus may result in sensory changes in the legs. • Dorsolumbar lordosis may cause pain because of traction on nerves or compression of nerve roots. • Edema involving the peripheral nerves may result in car- pal tunnel syndrome during the last trimester (Samuels & Niebyl, 2007). The syndrome is characterized by paresthe- sia (abnormal sensation such as burning or tingling) and pain in the hand, radiating to the elbow. The sensations are caused by edema that compresses the median nerve beneath the carpal ligament of the wrist. Smoking and alcohol con- sumption can impair the microcirculation and may worsen the symptoms. The dominant hand is usually affected most, although as many as 80% of women experience symptoms in both hands. Symptoms usually regress after pregnancy. In some cases, surgical treatment may be necessary (Samuels & Niebyl). Acroesthesia (numbness and tingling of the hands) is caused by the stoop-shouldered stance (see Fig. 13-12, B) assumed by some women during pregnancy. The condition is associ- ated with traction on segments of the brachial plexus. • Tension headache is common when anxiety or uncertainty complicates pregnancy. However, vision problems, sinusitis, or migraine also may be responsible for headaches. • "Light-headedness," faintness, and even syncope (fainting) are common during early pregnancy. Vasomotor instability, postural hypotension, or hypoglycemia may be responsible. • Hypocalcemia can cause neuromuscular problems such as muscle cramps or tetany.

parathyroid gland during pregnancy

Parathyroid hormone controls calcium and magnesium metabolism. Pregnancy induces a slight hyperparathy- roidism, a reflection of increased fetal requirements for calcium and vitamin D. The peak level of parathyroid hormone occurs between 15 and 35 weeks of gestation, when the needs for growth of the fetal skeleton are greatest. Levels return to normal after birth.

ballottement

Passive movement of the unengaged fetus is called______and can be identified generally between the sixteenth and eighteenth weeks. a technique of palpating a floating structure by bouncing it gently and feeling it rebound. In the technique used to palpate the fetus, the examiner places a finger in the vagina and taps gently upward, causing the fetus to rise. The fetus then sinks, and a gentle tap is felt on the finger

palmar erythema

Pinkish-red, diffuse mottling or well-defined blotches are seen over the palmar surfaces of the hands in about 60% of Caucasian women and 35% of African-American women during pregnancy. primarily related to increased estrogen levels

uteroplacental blood flow

Placental perfusion depends on the maternal blood flow to the uterus. Blood flow increases rapidly as the uterine size increases. Although uterine blood flow increases 20-fold, the fetoplacental unit grows more rapidly. Consequently, more oxygen is extracted from the uterine blood during the latter part of pregnancy. In a normal term pregnancy, one sixth of the total maternal blood volume is within the uterine vascular system. The rate of blood flow through the uterus ranges from 450 to 650 ml/min at term, and oxygen consumption of the gravid uterus increases to meet fetal needs. A low maternal arterial pressure, contractions of the uterus, and maternal supine position are three factors known to decrease blood flow. Estrogen stimulation may increase uterine blood flow. Doppler ultrasound examination can be used to measure uterine blood flow velocity, especially in pregnancies at risk because of conditions associated with decreased placental perfusion such as hypertension, intrauterine growth restriction, diabetes mellitus, and multiple gestation

A woman who has completed one pregnancy with a fetus (or fetuses) reaching the stage of fetal viability is called a:

Primipara A primipara is a woman who has completed one pregnancy with a viable fetus. To remember terms, keep in mind that gravida is a pregnant woman; para comes from parity, meaning a viable fetus; primi means first; multi means many; and null means none.

pulmonary function during pregnancy

Respiratory changes in pregnancy are related to the elevation of the diaphragm and to chest wall changes. Changes in the respiratory center result in a lowered threshold for carbon dioxide. The actions of progesterone and estrogen are presumed responsible for the increased sensitivity of the respiratory center to carbon dioxide. (Table 13-5 summa- rizes respiratory changes in pregnancy.) Although pulmonary function is not impaired by pregnancy, diseases of the respira- tory tract may be more serious during this time (Cunningham et al., 2010). One important factor responsible for this circum- stance may be the increased oxygen requirement

fluid and electrolyte balance during pregnancy

Selective renal tubular reab- sorption maintains sodium and water balance regardless of changes in dietary intake and losses through sweat, vomitus, or diarrhea. From 500 to 900 mEq of sodium is normally retained during pregnancy to meet fetal needs. To prevent excessive sodium depletion, the maternal kidneys undergo a significant adaptation by increasing tubular reabsorption. Because of the need for increased maternal intravascular and extracellular fluid volume, additional sodium is needed to expand fluid vol- ume and to maintain an isotonic state. As efficient as the renal system is, it can be overstressed by excessive dietary sodium intake or restriction or by use of diuretics. Severe hypovolemia and reduced placental perfusion are two consequences of using diuretics during pregnancy. The capacity of the kidneys to excrete water during the early weeks of pregnancy is more efficient than it is later in preg- nancy. As a result, some women feel thirsty in early pregnancy because of the greater amount of water loss. The pooling of fluid in the legs in the latter part of pregnancy decreases renal blood flow and GFR. This pooling of blood in the lower legs is sometimes referred to as physiologic edema or dependent edema and requires no treatment. The normal diuretic response to the water load is triggered when the woman lies down, preferably on her side, and the pooled fluid reenters general circulation. Normally the kidney reabsorbs almost all of the glucose and other nutrients from the plasma filtrate. In pregnant women, however, tubular reabsorption of glucose is impaired, so that glucosuria occurs at varying times and to varying degrees. Nor- mal values range from 0 to 20 mg/dl, meaning that during any day, the urine is sometimes positive and sometimes negative for glucose. In nonpregnant women, blood glucose levels must be at 160 to 180 mg/dl before glucose is "spilled" into the urine (not reabsorbed). During pregnancy, glucosuria (glycosuria) occurs when maternal glucose levels are lower than 160 mg/dl. Why glucose, as well as other nutrients such as amino acids, is wasted during pregnancy is not understood, nor has the exact mechanism been discovered. Although glucosuria may be found in normal pregnancies (2+ levels may be seen with increased anxiety states), the possibility of pregestational or ges- tational diabetes mellitus must be kept in mind. Proteinuria usually does not occur in normal pregnancy except during labor or after birth (Cunningham et al., 2010). However, the increased amount of amino acids that must be filtered may exceed the capacity of the renal tubules to absorb it; thus small amounts of protein are then lost in the urine. The amount of protein excreted is not an indication of the severity of renal disease, nor does an increase in protein excretion in a pregnant woman with known renal disease necessarily indi- cate a progression in her disease. However, a pregnant woman with hypertension and proteinuria must be carefully evaluated because she may be at greater risk for an adverse pregnancy out- come

cardiovascular anatomy changes during pregnancy

Slight cardiac hypertrophy (enlargement) is probably sec- ondary to the increased blood volume and cardiac output that occurs. The heart returns to its normal size after childbirth. As the diaphragm is displaced upward by the enlarging uterus, the heart is elevated upward and rotated forward to the left. The apical impulse, a point of maximal intensity (PMI), is shifted upward and laterally about 1 to 1.5 cm. The degree of shift depends on the duration of pregnancy and the size and position of the uterus.

supine hypotensive syndrome

Some degree of compression of the vena cava occurs in all women who lie flat on their backs during the second half of pregnancy. Some women experience a decrease in their systolic blood pressure of more than 30 mm Hg. After 4 to 5 minutes a reflex bradycardia is noted, cardiac output is reduced by half, and the woman feels faint. This condition is referred to as supine hypotensive syndrome

Braxton Hicks sign

Soon after the fourth month of pregnancy, uterine contractions can be felt through the abdominal wall. these contractions are irregular and painless and occur intermittently throughout pregnancy. These contractions facilitate uterine blood flow through the intervillous spaces of the placenta and thereby promote oxygen delivery to the fetus. Although these contractions are not painful, some women complain that they are annoying. After the twenty-eighth week these contractions become much more definite, but they usually cease with walking or exercise. these contractions can be mistaken for true labor; however, they do not increase in intensity or frequency or cause cervical dilation.

respiratory system changes during pregnancy

Structural and ventilatory adaptations occur during preg- nancy to provide for maternal and fetal needs. Maternal oxy- gen requirements increase in response to the acceleration in the metabolic rate and the need to add to the tissue mass in the uterus and breasts. In addition, the fetus requires oxygen and a way to eliminate carbon dioxide. Elevated levels of estrogen cause the ligaments of the rib cage to relax, permitting increased chest expansion (see Fig. 13-9). The transverse diameter of the thoracic cage increases by about 2 cm, and the circumference increases by 6 cm (Cunningham et al., 2010). The costal angle increases, and the lower rib cage appears to flare out. The chest may not return to its prepregnant state after birth (Seidel, Ball, Dains, Flynn, Solomon, & Stewart, 2011). The diaphragm is displaced by as much as 4 cm during pregnancy. As pregnancy advances, thoracic (costal) breathing replaces abdominal breathing, and it becomes less possible for the diaphragm to descend with inspiration. Thoracic breathing is accomplished primarily by the diaphragm rather than by the costal muscles (Blackburn, 2007). The upper respiratory tract becomes more vascular in response to elevated levels of estrogen. As the capillaries become engorged, edema and hyperemia develop within the nose, phar- ynx, larynx, trachea, and bronchi. This congestion within the tissues of the respiratory tract gives rise to several conditions commonly seen during pregnancy, including nasal and sinus stuffiness, epistaxis (nosebleed), changes in the voice, and a marked inflammatory response that can develop into a mild upper respiratory infection (Gordon, 2007). Increased vascularity of the upper respiratory tract also can cause the tympanic membranes and eustachian tubes to swell, giving rise to symptoms of impaired hearing, earaches, or a sense of fullness in the ears.

adrenal glands during pregnancy

The adrenal glands change little during pregnancy. Secretion of aldosterone is increased, resulting in reabsorption of excess sodium from the renal tubules. Cortisol levels also are increased

basal metabolic rate during pregnancy

The basal metabolic rate (BMR) increases during pregnancy. This increase varies consider- ably depending on the prepregnancy nutritional status of the woman and fetal growth (Blackburn, 2007). The BMR returns to nonpregnant levels by 5 to 6 days after birth. The elevation in BMR during pregnancy reflects increased oxygen demands. of the uterine-placental-fetal unit and greater oxygen consump- tion because of increased maternal cardiac work. Peripheral vasodilation and acceleration of sweat gland activity help dis- sipate the excess heat resulting from the increased BMR dur- ing pregnancy. Pregnant women experience heat intolerance, which is annoying to some women. Lassitude and fatigability after only slight exertion are experienced by many women in early pregnancy. These feelings, along with a greater need for sleep, may persist and may be caused in part by the increased metabolic activity.

circulation and coagulation time during pregnancy

The circulation time decreases slightly by week 32. It returns to near normal close to term. There is a greater tendency for blood to coagulate (clot) during pregnancy because of increases in various clotting fac- tors (factors VII, VIII, IX, X, and fibrinogen). This, combined with the fact that fibrinolytic activity (the splitting up or the dis- solving of a clot) is depressed during pregnancy and the post- partum period, provides a protective function to decrease the chance of bleeding but also makes the woman more vulnerable to thrombosis, especially after cesarean birth.

blood volume composition changes in pregnancy

The degree of blood vol- ume expansion varies considerably. Blood volume increases by approximately 1500 ml, or 40% to 45% above nonpregnancy levels (Cunningham et al., 2010). This increase consists of 1000 ml plasma plus 450 ml red blood cells (RBCs). The blood volume starts to increase at about the tenth to twelfth week, peaks at about the thirty-second to thirty-fourth week, and then decreases slightly at the fortieth week. The increase in volume of a multiple gestation is greater than that for a preg- nancy with a single fetus (Blackburn, 2007). Increased vol- ume is a protective mechanism. It is essential for meeting the blood volume needs of the hypertrophied vascular system of the enlarged uterus, for adequately hydrating fetal and mater- nal tissues when the woman assumes an erect or supine posi- tion, and for providing a fluid reserve to compensate for blood loss during birth and the puerperium. Peripheral vasodilation maintains a normal blood pressure despite the increased blood volume in pregnancy. During pregnancy there is an accelerated production of RBCs (normal, 4.2 to 5.4 million/mm3). The percentage of increase depends on the amount of iron available. The RBC mass increases by about 20% to 30% (Blackburn, 2007). Because the plasma increase exceeds the increase in RBC production, a decrease occurs in normal hemoglobin values (12 to 16 g/dl blood [non-pregnant]) and hematocrit values (37% to 47% [non-pregnant]). This state of hemodilution is termed physiologic anemia. The decrease is more noticeable during the second trimester than at other times, when rapid expansion of blood volume takes place faster than RBC production. A hemo- globin value that drops below 11 g/dl should be considered abnormal and often is due to iron deficiency anemia (Samuels, 2007). The total white cell count increases during the second tri- mester and peaks during the third trimester. This increase is primarily in the granulocytes; the lymphocyte count stays approximately the same throughout pregnancy. Table 13-3 lists the normal laboratory values during pregnancy.

pancreas during pregnancy

The fetus requires significant amounts of glucose for its growth and development. To meet its need for fuel, the etus not only depletes the store of maternal glucose but also decreases the mother's ability to synthesize glucose by siphon- ing off her amino acids. Maternal blood glucose levels decrease. Maternal insulin does not cross the placenta to the fetus. As a result, in early pregnancy the pancreas decreases its production of insulin. As pregnancy continues, the placenta grows and produces progressively greater amounts of hormones (i.e., hCS, estrogen, and progesterone). Cortisol production by the adrenals also increases. Estrogen, progesterone, hCS, and cortisol collectively decrease the mother's ability to use insulin. Cortisol stimulates increased production of insulin but also increases the mother's peripheral resistance to insulin (i.e., the tissues cannot use the insulin). Decreasing the mother's ability to use her own insulin is a protective mechanism that ensures an ample supply of glucose for the needs of the fetoplacental unit. The result is an added demand for insulin by the mother that continues to increase at a steady rate until term. The normal beta cells of the islets of Langerhans in the pancreas can meet this demand for insulin.

gallbladder and liver during pregnancy

The gallbladder is quite often distended because of its decreased muscle tone during pregnancy. Increased emptying time and thickening of bile caused by prolonged reten- tion are typical changes. These features, together with slight hypercholesterolemia from increased progesterone levels, may account for the development of gallstones during pregnancy. Hepatic function is difficult to appraise during pregnancy; however, only minor changes in liver function develop. Occa- sionally, intrahepatic cholestasis (retention and accumulation of bile in the liver, caused by factors within the liver) occurs late in pregnancy in response to placental steroids and may result in pruritus gravidarum (severe itching) with or without jaundice

musculoskeletal system changes during pregnancy

The gradually changing body and increasing weight of the pregnant woman cause noticeable alterations in her posture (Fig. 13-12) and the way she walks. The great abdominal dis- tention that gives the pelvis a forward tilt, decreased abdominal muscle tone, and increased weight bearing require a realign- ment of the spinal curvature late in pregnancy. The woman's center of gravity shifts forward. An increase in the normal lumbosacral curve (lordosis) develops, and a compensatory curvature in the cervicodorsal region (exaggerated anterior flexion of the head) develops to help her maintain her bal- ance. Aching, numbness, and weakness of the upper extremi- ties may result. Large breasts and a stoop-shouldered stance will further accentuate the lumbar and dorsal curves. Walk- ing is more difficult, and the waddling gait of the pregnant woman, called "the proud walk of pregnancy" by Shakespeare, is commonly seen. The ligamentous and muscular structures of the middle and lower spine may be severely stressed. These and related changes often cause musculoskeletal discomfort, especially in older women or those with a back disorder or a faulty sense of balance. Slight relaxation and increased mobility of the pelvic joints are normal during pregnancy. These adaptations permit enlargement of pelvic dimensions to facilitate labor and birth. The degree of relaxation varies, but considerable separation of the symphysis pubis and the instability of the sacroiliac joints may cause pain and difficulty in walking. Obesity and multife- tal pregnancy tend to increase the pelvic instability. Peripheral joint laxity also increases as pregnancy progresses, but the cause is not known (Murray & Hassall, 2009). The muscles of the abdominal wall stretch and ultimately lose some tone. During the third trimester, the rectus abdomi- nis muscles may separate (Fig. 13-13), allowing abdominal contents to protrude at the midline. The umbilicus flattens or protrudes. After birth, the muscles gradually regain tone; how- ever, separation of the muscles (diastasis recti abdominis) may persist.

increased sensitivity of vagina

The increased vascularity of the vagina and other pelvic viscera results in a marked increase in sensitivity. The increased sensitivity may lead to a high degree of sexual interest and arousal, especially during the second trimester of pregnancy. The increased congestion plus the relaxed walls of the blood vessels and the heavy uterus may result in edema and varicosi- ties of the vulva. The edema and varicosities usually resolve dur- ing the postpartum period.

operculum

The mucus fills the endocervical canal, resulting in the formation of the mucous plug aka "_______" This acts as a barrier against bacterial invasion during pregnancy.

venous changes in the breast during pregnancy

The richer blood supply causes the vessels beneath the skin to dilate. Once barely noticeable, the blood vessels become vis- ible, often appearing in an intertwining blue network beneath the surface of the skin. Venous congestion in the breasts is more obvious in primigravidas. Striae gravidarum may appear at the outer aspects of the breasts.

term

a pregnancy from the completion of 37 weeks of gestation to the end of week 42 of gestation

post date or post term

a pregnancy that goes beyond 42 weeks of gestation

preterm

a pregnancy that has reached 20 weeks of gestation but ends before completion of 37 weeks of gestation

leukorrhea

a white or slightly gray mucoid discharge with a faint musty odor. This copious mucoid fluid occurs in response to cervical stimulation by estrogen and progesterone. The fluid is whitish because of the presence of many exfoliated vaginal epithelial cells caused by the hyperplasia of normal preg- nancy. This vaginal discharge is never pruritic or blood stained. Because of the progesterone effect, ferning usually does not occur in the dried cervical mucus smear as it would in a smear of amniotic fluid. Instead a beaded or cellular crystallizing pattern is seen in the dried mucus

primipara

a woman who has completed one pregnancy with a fetus or fetuses who have reached 20 weeks of gestation

multipara

a woman who has completed two or more pregnancies to 20 or more weeks of gestation

multigravida

a woman who has had two or more pregnancies

nulligravida

a woman who has never been pregnant

nullipara

a woman who has not completed a pregnancy with a fetus or fetuses who have reached 20 weeks of gestation

gravida

a woman who is pregnant

primigravida

a woman who is pregnant for the first time

External structures of the perineum are enlarged during pregnancy because of

an increase in vasculature, hypertrophy of the perineal body, and deposition of fat. The labia majora of the nullipara approximate and obscure the vaginal introitus; those of the parous woman separate and gape after childbirth and perineal or vaginal injury.

Gravidity and parity

described with only two digits: the first digit represents the number of pregnancies the woman has had, including the present one; and parity is the number of pregnancies that have reached 20 or more weeks of gestation before the birth. For example, if the woman had twins at 36 weeks with her first pregnancy, parity would still be counted as one birth (gravida [G]1, para [P]1). If the woman becomes pregnant a second time, she would still be G2P1 until she gives birth at 38 weeks when she would then become G2P2.

why does the uterus normally rotate to the right as it elevates?

because of the presence of the rectosigmoid colon on the left side, but the extensive hypertrophy (enlargement) of the round ligaments keeps the uterus in the midline. Eventually the grow- ing uterus touches the anterior abdominal wall and displaces the intestines to either side of the abdomen. Whenever a pregnant woman is standing, most of her uterus rests against the anterior abdominal wall, and this contributes to altering her center of gravity.

how do pregnancy hormones prepare the vagina for labor and delivery?

by causing the vaginal mucosa to thicken, the connective tissue to loosen, the smooth muscle to hypertrophy, and the vaginal vault to lengthen.

viability

capacity to live outside the uterus; there are no clear limits of gestational age or weight. Infants born at 22 to 25 weeks of gestation are considered to be on the threshold of viability and are especially vulnerable to brain injury if they survive. Survival rates for infants with birth weights of less than 500 g is approximately 45%.

quickening

commonly described as a flutter and is difficult to distinguish from peristalsis. Fetal movements gradually increase in intensity and frequency. The week when quickening occurs provides a tentative clue in dating the duration of gestation.

Progesterone

essential for maintaining pregnancy by relaxing smooth muscles, resulting in decreased uterine con- tractility and prevention of miscarriage. Progesterone and estrogen cause fat to deposit in subcutaneous tissues over the maternal abdomen, back, and upper thighs. This fat serves as an energy reserve for both pregnancy and lactation. Estrogen also promotes the enlargement of the genitals, the uterus, and the breasts and increases vascularity, causing vasodilation. Estrogen causes relaxation of pelvic ligaments and joints. It also alters metabolism of nutrients by interfering with folic acid metabo- lism, increasing the level of total body proteins, and promoting retention of sodium and water by kidney tubules. Estrogen may decrease secretion of hydrochloric acid and pepsin, which may be responsible for digestive upsets such as nausea.

cholasma

facial melasma, mask of pregnancy, is a blotchy, brownish hyperpigmentation of the skin over the cheeks, nose, and forehead, especially in dark- complexioned pregnant women. appears in 50% to 70% of pregnant women, beginning after the sixteenth week and increasing gradually until term. The sun intensifies this pig- mentation in susceptible women. Caused by normal pregnancy usually fades after birth.

Human chorionic gonadotropin (hCG)

he earliest biochemical marker for pregnancy

mouth during pregnancy

he gums become hyperemic, spongy, and swollen during pregnancy. They tend to bleed easily because the increasing levels of estrogen cause selective increased vascular- ity and connective tissue proliferation (a nonspecific gingivitis). Epulis (discussed in the section on the integumentary system) may develop at the gumline.

Uterine enlargement is determined by

measuring fundal height, a measurement commonly used to estimate the duration of pregnancy. However, variation in the position of the fundus or the fetus, variations in the amount of amniotic fluid pres- ent, the presence of more than one fetus, maternal obesity, and variation in examiner techniques can reduce the accuracy of this estimation of the duration of pregnancy

A pregnant patient is experiencing some integumentary changes and is concerned that they may represent abnormal findings. The nurse provides information to the patient that the following findings would be considered "normal abnormal" findings during pregnancy so that she should not be alarmed.

melasma, linea nigra, vascular spiders Melasma (also known as the mask of pregnancy or chloasma), linea nigra (a hyperpigmentation line extending from the fundus to the symphysis pubis), and the presence of vascular spiders are all considered to be normal abnormal findings in pregnancy.

ausculatory changes during pregnancy

more audible splitting of S1 and S2, and S3 may be readily heard after 20 weeks of gestation. In addition, systolic and diastolic murmurs may be heard over the pulmonic area in some women. These are transient and disappear shortly after the woman gives birth.Between 14 and 20 weeks of gestation, the pulse increases about 10 to 15 beats/min, which then persists to term. Palpitations may occur. In twin gestations the maternal heart rate increases significantly in the third trimester. The cardiac rhythm may be disturbed. The pregnant woman may experience sinus arrhythmia, premature atrial contrac- tions, and premature ventricular systole. In the healthy woman with no underlying heart disease, no therapy is needed; however, women with preexisting heart disease will need close medical and obstetric supervision during pregnancy

friability

tissue is easily damaged increased can cause slight bleeding after coitus with deep penetration or after vaginal examination.

Serum and urine pregnancy tests

performed in clinics, offices, women's health centers, and laboratory settings, and urine pregnancy tests may be performed at home. Both serum and urine tests can provide accurate results. A 7- to 10-ml sam- ple of venous blood is collected for serum testing. Most urine tests require a first-voided morning urine specimen because it contains levels of hCG approximately the same as those in serum. Random urine samples usually have lower levels. Urine tests are less expensive and provide more immediate results than do serum tests

linea nigra

pigmented line extending from the symphysis pubis to the top of the fundus in the midline; this line is known as the linea alba before hormone-induced pigmentation. In primigravidas the extension of the _____, beginning in the third month, keeps pace with the rising height of the fundus; in multigravidas, the entire line often appears earlier than the third month. Not all pregnant women develop this, and some women notice hair growth along the line with or without the change in pigmentation.

Gravidity

pregnancy

hCG info

pregnancy tests are based on the recognition of hCG or a beta (β) subunit of hCG. Pro- duction of β-hCG begins as early as the day of implantation and can be detected as early as 7 to 10 days after conception (Black- burn, 2007). The level of hCG increases until it peaks at about 60 to 70 days of gestation and then declines until about 80 days of pregnancy. It remains stable until about 30 weeks and then gradually increases until term. Higher than normal levels of hCG may indicate abnormal gestation (e.g., a fetus with Down syndrome) or multiple gestation; an abnormally slow increase or a decrease in hCG levels may indicate ectopic pregnancy or impending miscarriage

Human chorionic somatomammotropin (hCS)

previously called human placental lactogen, is produced by the placenta and has been suggested to act as a growth hormone and con- tribute to breast development. It also may decrease the maternal metabolism of glucose and increase the amount of fatty acids for metabolic needs; however, its function is poorly understood

Serum prolactin

produced by the anterior pituitary begins to increase early in the first trimester and increases progressively to term. It is responsible for initial lactation; however, the high levels of estrogen and progesterone inhibit lactation by block- ing the binding of prolactin to breast tissue until after the birth

oxytocin

produced by the posterior pituitary in increas- ing amounts as the fetus matures. This hormone can stimulate uterine contractions during pregnancy, but high levels of pro- gesterone prevent contractions until near term. Oxytocin also stimulates the let-down or milk-ejection reflex after the birth in response to the infant's sucking at the mother's breast and dur- ing sex play if the mother's nipples are stimulated .

Epulis

red, raised nodule on the gums that bleeds easily. This lesion may develop around the third month and usually continues to enlarge as pregnancy progresses. It is usually managed by avoiding trauma to the gums (e.g., using a soft toothbrush). An epulis usually regresses spontaneously after birth.

Radioreceptor assay (RRA)

serum test that measures the ability of a blood sample to inhibit the binding of radiolabeled hCG to receptors. The test is 90% to 95% accurate from 6 to 8 days after conception

pruritus gravidarum

severe itching in pregnancy

uterine souffle

sound made by blood in the uterine arteries that is synchronous with the maternal pulse

funic souffle

sound made by blood rushing through the umbilical vessels and synchronous with the fetal heart rate

Uterus changes during pregnancy

stimulated by high levels of estrogen and progesterone. Early uterine enlargement results from increased vascularity and dilation of blood vessels, hyperplasia (production of new muscle fibers and fibroelastic tissue) and hypertrophy (enlargement of preexisting muscle fibers and fibroelastic tissue), and development of the decidua. By 7 weeks of gestation, the uterus is the size of a large hen's egg; by 10 weeks of gestation, it is the size of an orange (twice its nonpregnant size); and by 12 weeks of gestation, it is the size of a grapefruit. After the third month, uterine enlargement is primarily the result of mechanical pressure of the growing fetus. As the uterus enlarges it also changes in shape and position. At conception the uterus is shaped like an upside-down pear. During the second trimester, as the muscular walls strengthen and become more elastic, the uterus becomes spherical orglobular. Later, as the fetus lengthens, the uterus becomes larger and more ovoid and rises out of the pelvis into the abdominal cavity. The pregnancy may "show" after the fourteenth week, although this depends to some degree on the woman's height and weight. Abdominal enlargement may be less apparent in the nullipara with good abdominal muscle tone (Fig. 13-2). Posture also influences the type and degree of abdominal enlargement that occurs. In normal pregnancies, the uterus enlarges at a pre- dictable rate. As the uterus grows it may be palpated above the symphysis pubis some time between the twelfth and fourteenth weeks of pregnancy (Fig. 13-3). The uterus rises gradually to the level of the umbilicus at 22 to 24 weeks of gestation and nearly reaches the xiphoid process at term.

Radioimmunoassay (RIA)

tests for the beta sub-unit of hCG in serum or urine samples use radioactively labeled markers and are usually performed in a laboratory. These tests are accurate with low hCG levels (5 milli-International Units/ ml) and can confirm pregnancy before the first menstrual period. Results are available within a few hours

Colostrum

the creamy white-to-yellowish-to-orange pre-milk fluid, may be expressed from the nipples as early as 16 weeks of gestation

Enzyme-linked immunosorbent assay (ELISA)

the most popular method of testing for pregnancy. It uses a spe- cific monoclonal antibody (anti-hCG) with enzymes to bond with hCG in urine. As an office or home procedure, it requires minimal time and offers results in less than 5 minutes. A posi- tive test result is indicated by a simple color-change reaction. Depending on the specific test, levels of hCG as low as 25 milli- International Units/ml can be detected as early as 7 days after conception -Basis for most over-the-counter home pregnancy tests. With these one-step tests, the woman usually applies urine to a strip and reads the results. The test kits come with directions for collection of the specimen, the testing procedure, and reading of the results. A positive test result is indicated by a simple color change reaction or a digital reading.

parity

the number of pregnancies in which the fetus or fetuses have reached 20 weeks of gestation when they are born, not the number of fetuses (e.g., twins) born. Whether the fetus is born alive or is stillborn (fetus who shows no signs of life at birth) does not affect parity


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