chapter 11: pregnancy, labor and delivery
why does a woman not want to "bear down" or push until the cervix is completely dilated?
Bearing down is not helpful, may cause cervical lacerations
what is effacement? (pre-labor)
Each contraction shortens the muscle fibers in the cervix thinning the cervix
when is the most critical period of development? why?
The first trimester is a critical period of development because of the great sensitivity of the embryo and fetus to teratogens (agents that can cause malformations and birth defects)
why are babies of multiple pregnancies born at lower birth weight than singleton babies?
The placentas of multiple pregnancy preagncies have to compete for physical space and nutrients in the uterus
when has the baby crowned what is restitution of the head?
When the top of the head no longer regress between contraction
gestation
gestation period is the time that the developing fetus spends in the uterus before being born.
is pregnancy a normal physiological condition or an illness?
pregnancy is normal physiological condition not an illness
Edema
swollen feet
Be able to distinguish between the 4 uterine signs of pregnancy
Hagar's sign: the softening of the neck or isthmus of the uterus, the narrowest part between the body and the cervix; first detectable at 6 weeks, later disappears when the entire cervix and the uterus have become soft and spongy in consistency
Understand the positive feedback cycle between the cervix and the pituitary gland and oxytocin.
Head of the baby buses against the cervix-> nerve impulses from cervix are transmitted to the mother's brain-> brain stimulates pituitary land to secrete oxytocin-> oxytocin stimulates uterine contractions and pushes baby towards cervix-> head of baby pushes against cervix->->-> contractions build until the baby is delivered and the positive feedback is broken
understand the difference between using the date of conception vs the woman's last period in determining due date.
If the woman knows the date of conception, she can, based on statical averages, expect to deliver the baby 266 days or 38 weeks later. The usual method is to predict a due date from the first day of last menstrual period and add 280 weeks on either side of an estimated due date
(Maternal changes during pregnancy). Uterus: how much larger is full term uterus vs a non pregnant uterus? how does blood flood change? when does the uterus expand outside of the pelvic cavity into abdominal cavity? when is a woman "obviously" pregnant?
At full term, a pregnant uterus weighs around one kilogram (2.2 lbs) and is about 5x-6x larger than a non pregnant uterus. Blood vessels also elongate, dilate and form new branches to support and nourish the growing muscle tissue= dramatic increase in the uterine blood flow. During the first 3 week, the entire uterus remains in the pelvic cavity- after that time, the funds expands, pushing into abdominal cavity. The expanding uterus usually becomes obvious around the 4th or 5th month
Be able to distinguish between the 4 uterine signs of pregnancy
Chadwick's sign: the walls of the vagina change from usual pink to a dusty bluish color due to the increased blood supply and venous congestion. ( however, such a color change may be present with heart disease or pelvic tumor
what happen to he mucus plug? what is the name for when a little blood accompanies the plug? (pre-labor)
Loss of mucus plug,Effacement and dilation of the cervix causes the fetal membranes attached to the uterine wall at the region of the internal los to become loosened -> pull away from the uterine wall and the mucous plug is released. The blood that accompanies the mucus plug is called bloody show.
Be able to distinguish between the 4 uterine signs of pregnancy
Piskacek's sign: appears after implantation of the fertilized egg as a soft bulge at the implantation site.
After delivery, at what level should the baby be kept? why? should the cord be cut immediately?
The baby should be kept below the level of the uterus for a minute or so to allow an adequate amount of the placental blood to transfuse the infant- should not cut the cord for a few minutes to allow this transfer to occur
what is transition? which is the most difficult phase of a woman's labor? which is the shortest?
Transition is The most difficult and shortest phase for the woman=last approximately 1 hour in the first delivery and 15-30 minutes in successive births. At transition the contractions are stronger, more painful, somewhat reactive an last longer
Understand what APGAR score is used to evaluate. what do the letters mean? do you want a high or low score?
Activity Pulse Grimace Appearance Respiration. a score of 7-10 means the baby is in the best possible condition, 3-6 means moderately degreased. a score of 2 indicated problems.
what is the difference between brixton-hicks pre-labor contractions and true labor contractions?
Braxton-hicks pre labor contractions=regularity and discomfort, true labor painful, occurs less than 10 minutes apart. last 30 minutes and regular frequency
Be able to distinguish between the 4 uterine signs of pregnancy
Goodall's sign: a softening of the cervix; appears early in pregnancy
Maternal changes in cervix: what is a mucus plug? what hormone causes it to be created? when is it created? is it acidic or basic-to help prevent bacterial infection?
The cervical mucus is quit acidic to also help prevent bacterial infection. it is made by the 6 week of pregnancy
Understand the signs used to determined pregnancy-both before and after pregnancy test were developed
signs used to establish if a woman was pregnant before pregnancy test were developed; absence of menstruation-usually the first sign noticed. Morning nausea, fatigue, breast tenderness and increased frequency of urination. change in size and shape. A suntan elevation of the basal body temperature. Pregnancy test detect hug levels which indicate that implantation has occurred
what is the average duration for the first stage of labor with a woman's first baby?
12 hours but there are wide variations
when does the 1st stage of true labor begin and end? how large does the cervix deflate?
1st stage begins with the first true labor contractions and ends with the complete dilation of the cervix-large enough to permit the passage of the infant
when does the 2nd stage of true labor end?
2nd stage ends with the delivery of the infant
Maternal change to the digestive system: what percent of woman experience morning sickness? when does the morning sickness normally subside? does it just happen in the morning? what is the one "good thing" about morning sickness? Be aware of the change in saliva, heart burn, constipation and gas that also occur during pregnancy
80% of woman experience morning sickness. Subside after week 16 of their pregnancy 20% last throughout pregnancy. Morning sickness can be presented at any time. Excessive heart salvation, heart burn- especially during the last 3 months-due to relaxation of muscle tone and increased intra-abdominal pressure, constipation and flatulence gas due to the decreased muscle tone in large intestine.
when does the 3rd stage of true labor start and end?
After delivery of the baby, uterine contractions sow for a short time and the begin again to deliver the placenta-has become partially separated from the uterus
understand the characteristics that increase the incidence of conceiving fraternal twins
Age and Reproductive history of mother: likelihood of twins increases with age. once woman's given birth to twins, a multiple birth is 5x more likely to occur the next time. woman between age 35-40 who have had 4 or more children are 3x more likely to have twins than younger woman without children. Heredy: woman who have fraternal twins or have a family history of fraternal twins are more likely to conceive twins. Ethnic background: woman of African descent are more likely to have twins than are woman of european descent. Asian descent are the least likely to have twins. Maternal wight and height: Larger and taller woman are more likely to have twins than smaller woman. Infertility treatments: woman who have undergone infertility treatments, including assisted reproductive technology are more likely to have twins
(maternal change)Respiratory system: how do anatomical changes that occur in pregnancy affect breathing? when does this change subside?
Anatomical changes occur later in pregnancy that affect breathing-> uterus pushes up on the diaphragm and elevates it but the entire thoracic cavity compensates by an increased in it dimensions so more air can be inspired. Usually subside when the fetal head shifts into the true pelvis (lightening), when the uterus drops slighly= reduces the pressure on the diaphragm
Be able to compare and contracts dizygotic or fraternal twins with monozygotic or identical twins, what are conjoined or siamese twins?
Dizygotic or Fraternal twins are the most common type of multiple pregnancy. Occurs when 2 eggs are simultaneously ovulated from two separated follicles and are then fertilized by two different sperm. the two zygotes implant in separate areas in the uterus. may be the same or opposite sex. resemble each other as much as any other sibling would. Monozygotic or identical twins: originated from one fertilized egg that splits into two zygotes early in development. are the same sex. begin their lives genetically identical. born identical in physical appearance unless there has been some environmental factor during fetal life to cause a difference between them. Conjoined or siamese twins: develop when monozygotic twins fail to separate completely
Musculosketal changes during pregnancy: what hormones cause ligaments holding the Sacroiliac joints and public symphysis to soften and stretch? what happens to a woman's center of gravity? what does this do to her posture? what happens to a woman's leg muscles and her hands?
By the 10-12th week of pregnancy, the hormones estrogen, progesterone, and relaxing cause the ligaments that hold the sacroiliac joints and the public symphysis in place begin to soften and stretch= preparing for an easier deliver. Shifts in a woman's center of gravity caused by the growing fetus may alter balanced and affect a woman's walk= waddle. Posture change in pregnancy include an increased swayback and upper spine extensions to compensate for enlarging abdomen, coupled with loosening sl joints may result in lower back pain. Legs cramps are common during the last few months of pregnancy. 50% of woman experience occasional sensation in the hands- from tingling to pain
maternal changes (ovaries) when does the corpus luteum secrete progesterone? what organ takes over progesterone production and secretion? when?
Corpus luteum secrete progesterone during the first trimester, the placenta takes over the major production and the corps luteum regress
Varicose veins:
Enlarged and twisted veins; in the leg and vulva are common during pregnancy flow of venous blood-> blood backs up in the veins of the leg and exerts increasing pressure on their walls= they stretch and thin
cardiovascular system (materiaal changes): how does blood volume change? what can this lead to? what mineral is required for RBC production? how does increased blood volume affect blood flow to the extremities? risks of anemia? varicose veins? hemorrhoids?
Enlarging uterus and placenta demand more blood and more oxygen. Heart works harder and pumps more blood peer minute. increase blood volume (45-50%). May lead to generalized edema= swollen ankles and fingers occur quite often. Number of red blood cells also increases -> increases need for iron to make the RBCs. Blood flow to the extremities increases-> woman who have always had cold hands and feet will find them uncharacteristically warm. pregnant woman are at an increased risk for anemia= low RBC number.
during which stage do the fetal membranes usually rupture? what are the forewaters? the hindwaters?
Fetal membrane usually rapture during the first stage of labor. foresters is a little pocket of fluid called the firewater that lies in front of the fetal head. The rest of the fluid remains behind the baby's head is the hinderwater
What nutritional requirements are increased during pregnancy-> folic acid for neural tube development, vitamin b12& iron for RBC production, calcium for bones. should these only be taken while pregnant? what about before or when breastfeeding?
Folic acid: vitamin shown to play a role in preventing neutral tube disorders- birth defect in which the brain and spinal cord of the developing embryo do not properly. vitamin B12 & iron demand increases to meet the demands of manufacturing red blood cells. mayo clinic recommends follicle acid and iron and calcium (especially during 3rd trimester when baby's bones are rapidly growing and strengthening). Should start taking before conception and take throughout pregnancy and keep taking while breastfeeding
Weight gain: on a average, how much weight should a woman gain? what happens of she gains too little or too much weight? how long after delivery should she expect to get rid of this extra weight? how long does breastfeeding affect weight loss?
The amount of weight that a woman should gain depends on her weight and body size before pregnancy, and on the number of fetus she is carrying. Too little wight increased risk of delivering a baby of low with weight, may also reduce cell size and number of fetal tissues, with disproportionate effects occurring in the brain. A woman who gains too much weight during pregnancy can also lead to problems, macrosomia: babies weight 8.8 lbs or more- linked to an increased need for a cesarean section as well as other complication. The rest of the weight will likely be gone by 3 months after delivery, especially if she is breastfeeding
know the risks to the fetus as well as to the mother of multiples
The risks to the mother and the developing fetus increases with number developing in the uterus at the same time. Twins are 7x more likely than singletons to die during their first month. Triplets are 20x more likely than singletons to die during their first month
maternal changes in breast: How do the breasts change in size, tenderness, and consistency? what happens to the areola? at what time can colostrum be expressed from the nipples?
Tingling and soreness are common in the first two months-then the breast become enlarged, more tender, and nodular. The primary areolae becomes wider and deepen in color and nipples enlarge. Colostrum can be express by the 10th week
Understand pre-labor events (lighting) what is the normal fetal position for delivery? what does that mean? what changes happen to mom after the baby has dropped?
Towards the end gestation, the fetus usually shifts position within the uterus in preparation for its descent through the birth canal=lightning .Changes to both expectant mother and the fetus that occur in the days or weeks before parturition (child birth)
maternal changes to the urinary system: how does urinary frequency change and why? what hormone is associated with this change?
Urinary frequency increases due to pressure from the enlarging uterus on the bladder and hormonal shifts. Placenta lactogen triggers and increase in urine production
what is the main cause of postpartum hemorrhaging? what does the doctor/ nurse do if the infant is unable to nurse immediately after delivery? what should a mom do if she experiences postpartum hermorrhagia at home?
Uterine atony or lack of contractions, if infant is not able to nurse immediately after delivery, it may be necessary to massage the abdomen and the uterus to maintain contractions until the placenta is delivered. if you experience bleeding after you have gone home, having the baby nurse will cause the same effect and save your life.
Hemorrhoids
Varicose veins of the rectum-very common during pregnancy aggravated by constipation- may cause bleeding
what is quickening and when does it occur?
a fluttering sensation known as quickening or a feeling of life. begins 16-18 weeks
what is the ferguson reflex? what does birth canal consist of at the beginning of 2nd stage of labor?
abdominal muscles, birth canal at the beginning of labor consists of completely dilated cervix, distended vagina, stretch and sit ended muscles of the pelvic floor.
According to WHO, how long is a full term pregnancy? what is pre-term vs. post-term pregnancy ( in weeks)? how many week, on a average, does a pregnancy last?
full term pregnancy is 37-42 weeks. Infants delivered before 37 weeks are considered preterm. Gestation longer than 42 weeks are consider post term. pregnancy last on a average of 40 weeks.
know how long the average hospital stay after delivery was during 1950s&1960s, the 1970s, the 1980s. what about during the mid 1990s? what is the newborn and mother's health protection act of 1996? how long must insurance companies allow a woman to stay after vaginal birth?
in the 1950s and 1960s- common for hospital stays to last a week or 10 days in the us, by 1970, 4 days in the hospital was average, by 1980 the average sat was 3.2 days. 1996 newborns and mothers health protection act- federal legislation was passed= prohibited insurance companies from restricting post delivery hospital stays after vaginal birth to fewer than 48 hours. for healthy woman with uncomplicated deliveries having their 2nd or 3rd baby, 24 hour stay may be all they need or want. first time mothers with a longer labor and more questions concerning baby and breast- feeding, may want or need more care.
what is ballottement? understand the difference between internal and external
internal ballottement: can be performed by 14 weeks during a vaginal exam-with the finger up against the cervix, the cervix is gently tapped-> the fetus within the amniotic sac bounces up against the top of the uterus, and as it sinks back down, the rebound is felt against the finger. By 24 weeks, an external ballottement can be performed= a push on one side of the abdomen with one hand will cause the fetus to move to the other side and can be felt by a hand that is placed there
what percent of deliveries actually occur on their estimated due date? by how much are they generally off ( 2 weeks)?
less than 5%. generally off by 2 weeks
lightening
lightening is experience severe weeks before labor with the first baby but usually takes place during labor in a woman who has already borne a child
maternal changes to the integumentary system: how are stretch marks created? how might a woman's complexion change?her hair and nails?
stretch marks ( strait gravidarum) of change in the collagen and elastic fibers in the dermis of the skin-result from relatively rapid weight gain of pregnancy. Some woman develop irregular patches of freckles on the forehead and cheeks that form the mask of pregnancy or chloasma. increased pigmentation also occurs on the breasts and generals, dark-haired woman may get a brownish-black line appearing down the middle of the abdomen. spider veins. Hoar normally undergoes a growing and a resting phase is followed by a loss of hairs, which are then replaced by new ones. Acceleration in fingernail and hair growth: result of an increased metabolism due to thyrotropin
what causes the following pains or discomforts during delivery-cramps,intense backache or back labor, the ring of fire?
uterine contractions- are similar but also different from other smooth muscle contraction pain you may have experienced (menstrual or intestinal cramps). the peak discomfort of labor contractions only last a few second and disappears between contraction and disappear between contraction. cervical dilation-stimulates nerves that cause sensation in the sacral region=intense backache. stretching of the vagina and perineum, when a full term baby's head start its descent into the both canal, it creates pressure on the bladder, rectum, and all the surrounding tissues-> may be interpreted as pain