13.14 Birth and Lactation

Question 1

What is parturition?

Answer 1

birth

Question 2

What is parturition dependent on?

Answer 2

contraction of the uterine wall

Question 3

What hormone throughout pregnancy helps repress contractions?

Answer 3

progesterone

Question 4

What are the three reasons uterine excitability increases at the end of pregnancy?

Answer 4

1. change in estrogen/progesterone ratios
2. presence of oxytocin
3. mechanical stretching of uterus and cervix

Question 5

What is the positive feedback reflex for uterine contractions?

Answer 5

increased pressure on cervix causes pituitary gland to release oxytocin which causes uterine contractions and a further increase of pressure on cervix leading to more oxytocin, stronger contractions, and more pressure on cervix

Question 6

What is the first stage of labor?

Answer 6

dilation of cervix

Question 7

What is the second stage of labor?

Answer 7

movement of baby through cervix and birth canal

Question 8

What is the third stage of labor?

Answer 8

expulsion of placenta

Question 9

What hormones inhibit the release of prolactin?

Answer 9

estrogen and progesterone

Question 10

What does suckling of the nipple cause?

Answer 10

stimulates the pituitary gland to release surge of prolactin
stimulates release of oxytocin necessary for milk let down