Lec 30 Physiology of pregnancy Flashcards
(29 cards)
When does embryonic criculation begin?
- when placenta forms
- about 21 days
What are the 4 functions of placenta
- provide maternal nutrients and O2 to fetus
- clear fetal waste
- confer passive immunity by transfer of maternal antibodies
- produce hCG, hPL, estrogen, progesterone
What are 2 actions of hCG? what produces it?
- maintains corpus luteum
- causes maternal nausea
produced by placenta
What is action of progesterone in placenta?
- smooth muscle relaxation
- maintains relaxation of uterus, bronchioles [pregnant woman has improved asthma over pregnancy] so can inhale more oxygen, Gi relaxation [so more time for absorption of nutrients]
What is action of human placental lactogen [HPL]? what produces it?
- breast growth and lactation
- diabetogenic = increases insulin resistance in mother, so frees up glucose for fetus that needs it for energy
- lipolytic: mobilizes free fatty acids in maternal plasma for more maternal energy
produced by placenta
What changes to circulatory system occur to pregnant woman?
- increased venous return
- increased CO
- increased blood volume
- decreased blood pressure
What change to respiratory system occur to pregnant woman?
- increased oxygen consumption
What change to urinary system occur to pregnant woman?
- more renal blood flow, more urine formation
- mother needs to clear metabolic by products from both fetus and mother
What change to digestive system occur to pregnant woman?
- increased nutrient transit time, food moves slower so better absorption but constipation
what happens to pituitary gland in pregnancy? what affect from PP and from AP?
- growth of pituitary
PP:
- increased oxytocin [mainly in labor and lactation]
AP:
- increased prolactin, corticotropin, thyrotropin, GH
- decreased FSH , LH
What is function of oxytocin?
- causes muscle contractions
- involved in uterine contractions of labor
- causes contraction of breast myoepithelial cells so can eject milk
What happens to adrenal gland in pregnancy?
- increased cortical secretion
- mobilizes AA for fetus
- sodium resportion causes fluid retention
What happens to thyroid gland in pregnancy?
- enlarged
- increased TH production
What happens to parathyroid in pregnancy
- enlarged
- causes Ca resorption from maternal bones if needed by fetus
When can you determine gender of fetus?
18-20 wks
What is normal amount of weight gain in pregnancy? breakdown of where it comes from?
total 25ish pounds
13 pounds: mother
6-9 pounds: fetus
4 pounds: placenta/membranes/fetus
What is leopold’s manuever?
to determine position of fetus
3 stages of labor
frist stage: onset labor contractions to full dilation of cervix
second stage: full cervix dilation to delivery of fetus
third stage: delivery of baby to delivery of placenta
What is effect of stretch of uterine smooth musculature?
- stretching by fetal growth causes increased contractility
what is effect of stretch of uterine cervix?
- feedback mech from cervix, increases contractions
What is effect of estrogen on parturition?
increases uterine contractility
what is effect of progesterone on parturition?
decreases uterine contractility
How does estrogen/progesterone ratio change in pregnancy?
increases near term
What is effect of oxytocin on parturition?
increases contractions in labor
