Lec 30 Physiology of pregnancy

Question 1

When does embryonic criculation begin?

Answer 1

• when placenta forms

- about 21 days

Question 2

What are the 4 functions of placenta

Answer 2

• provide maternal nutrients and O2 to fetus
• clear fetal waste
• confer passive immunity by transfer of maternal antibodies
• produce hCG, hPL, estrogen, progesterone

Question 3

What are 2 actions of hCG? what produces it?

Answer 3

• maintains corpus luteum
• causes maternal nausea

produced by placenta

Question 4

What is action of progesterone in placenta?

Answer 4

• 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]

Question 5

What is action of human placental lactogen [HPL]? what produces it?

Answer 5

• 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

Question 6

What changes to circulatory system occur to pregnant woman?

Answer 6

• increased venous return
• increased CO
• increased blood volume
• decreased blood pressure

Question 7

What change to respiratory system occur to pregnant woman?

Answer 7

• increased oxygen consumption

Question 8

What change to urinary system occur to pregnant woman?

Answer 8

• more renal blood flow, more urine formation

- mother needs to clear metabolic by products from both fetus and mother

Question 9

What change to digestive system occur to pregnant woman?

Answer 9

• increased nutrient transit time, food moves slower so better absorption but constipation

Question 10

what happens to pituitary gland in pregnancy? what affect from PP and from AP?

Answer 10

• growth of pituitary

PP:
- increased oxytocin [mainly in labor and lactation]

AP:

• increased prolactin, corticotropin, thyrotropin, GH
• decreased FSH , LH

Question 11

What is function of oxytocin?

Answer 11

• causes muscle contractions
• involved in uterine contractions of labor
• causes contraction of breast myoepithelial cells so can eject milk

Question 12

What happens to adrenal gland in pregnancy?

Answer 12

• increased cortical secretion
• mobilizes AA for fetus
• sodium resportion causes fluid retention

Question 13

What happens to thyroid gland in pregnancy?

Answer 13

• enlarged

- increased TH production

Question 14

What happens to parathyroid in pregnancy

Answer 14

• enlarged

- causes Ca resorption from maternal bones if needed by fetus

Question 15

When can you determine gender of fetus?

Answer 15

18-20 wks

Question 16

What is normal amount of weight gain in pregnancy? breakdown of where it comes from?

Answer 16

total 25ish pounds

13 pounds: mother

6-9 pounds: fetus

4 pounds: placenta/membranes/fetus

Question 17

What is leopold’s manuever?

Answer 17

to determine position of fetus

Question 18

3 stages of labor

Answer 18

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

Question 19

What is effect of stretch of uterine smooth musculature?

Answer 19

• stretching by fetal growth causes increased contractility

Question 20

what is effect of stretch of uterine cervix?

Answer 20

• feedback mech from cervix, increases contractions

Question 21

What is effect of estrogen on parturition?

Answer 21

increases uterine contractility

Question 22

what is effect of progesterone on parturition?

Answer 22

decreases uterine contractility

Question 23

How does estrogen/progesterone ratio change in pregnancy?

Answer 23

increases near term

Question 24

What is effect of oxytocin on parturition?

Answer 24

increases contractions in labor

Question 25

what is effect of prostaglandins on parturition?

Answer 25

• softens cervix

- causes contractions

Question 26

breastfeeding

Answer 26

• suckling on nipple stimulates brain for more milk production
• small volume of milk initially [colostrum] full of fat and antibodies
• uterine contractions occur with infant’s suckling

Question 27

What stimulates lactation?

Answer 27

• prenatally: placental estrogen stimulates prolactin, prolactin causes growth mammary glands and milk production
• postpartum infant suckling causes oxytocin secretion from PP
• oxytocin causes initial ejection of milk
• prolactin causes continued secretion of milk

Question 28

What is mastitis? cause? treat? can you breastfeed?

Answer 28

• inflammation
• caused by staph or strep from nursing baby
• treat with antibiotics
• can continue breastfeeding

Question 29

What is a breast abscess? treat? can you breastfeed?

Answer 29

• forms in 10% of women with mastitis
• requires surgical drainage
• need cessation breastfeeding on that side