Reproductive and Integrative Physiology

Question 1

Timelines for birth

Answer 1

• 40 weeks after last normal menstrual period
• 38 weeks after fertilization
• Preterm birth is anything before 34 weeks
• Gestation is 40 weeks

Question 2

What is a zygote?

Answer 2

• cell when the egg is fertilized by the sperm

Question 3

What is a blastocyst?

Answer 3

• embryo 5 days post-fertilization
• attaches to lining of the uterus

Question 4

What does the placenta do?

Answer 4

• takes waste CO2 and provides O2
• produces hormones (hCG)
• hCG stimulates the placenta to create progesterone

Question 5

What do relaxin and progesterone do?

Answer 5

• causes joints around pelvis to relax and cervix to dilate
• progesterone prevents early contraction of uterus and strengthen pelvic wall muscles

Question 6

Explain the oxytocin feedback loop

Answer 6

• positive feedback loop
• oxytocin released during labor and delivery
• causes uterine muscles to contract
• nerve impulses then go to brain and more oxytocin is released

Question 7

What does the pituitary gland do during pregnancy?

Answer 7

• increase in prolactin release from anterior pituitary
• anterior pituitary also releases colostrum (liquid gold)
• posterior pituitary also releases oxytocin (for labor)

Question 8

Cardiovascular changes during pregnancy

Answer 8

• increased blood volume = increased cardiac output
• increased vasodilation

Question 9

What does the placenta do in regards to activity with the corpus luteum?

Answer 9

• placenta makes new hormones to support pregnancy
• corpus luteum does not regress (stop making progesterone) until placenta is functional

Question 10

How does placenta develop with focus on circulation and exchange with baby?

Answer 10

• placenta forms from both maternal and fetal side
• maternal side provides lacunae (pools of blood)
• fetal side provides chorionic villi
• gas exchange and nutrient exchange occurs across chorionic villi membrane with lacunae

Question 11

Renal changes associated with pregnancy

Answer 11

• increased GFR
• increase in RAAS (renin-angiotensin-aldosterone system)
• increase in urination

Question 12

Respiratory changes in pregnancy

Answer 12

• increased alveolar ventilation
• increased tidal volume
• increased PO2 and decreased PCO2
• decrease in residual volume

Question 13

When is a fetus most susceptible to abnormal development?

Answer 13

• weeks 3 to 8

Question 14

Changes in fetal growth based on each trimester

Answer 14

T1- organ development (most susceptible to abnormal development)
T2 - length
T3 - weight