Lecture 23- Puerperium and Lactation

Question 1

Puerperium

Answer 1

is the period postpartum when the reproductive tract returns to its nonpregnant condition so that the female may become pregnant again.
it is initiated immediately after parturition and lasts until reproductive function is re-established

Question 2

Lactation

Answer 2

is the synthesis , secretion and removal of milk from the mammary gland for the nourishment and survival of the newborn.
it is initiated immediately after parturition and lasts until weaning of the offspring (or dry off in dairy females)

Question 3

Main Events in Puerperium

Answer 3

1. expulsion of the fetal membranes and lochia
2. uterine involution and endometrial repair
3. elimination of microbial contamination of the reproductive tract
4. resumption of regular ovarian function and estrous cyclicity

Question 4

Expulsion of fetal membranes

Answer 4

1. maturation of chorionic villi prepartum- periparturitent endocrine changes lead to activation of collagenases
2. myometrium contractions and vasoconstrictions-helps release placenta
3. recognition of fetal membrane as foreign
4. migration of neutrophils
5. detachment of chorionic villi
6. expulsion of the fetal membranes

failure: retained fetal membranes (>12 hrs in ruminants, >3hrs in mares)

Question 5

Lochia

Answer 5

amniotic and allantoic fluid , blood, placenta, cellular debris

Question 6

Resumption of Estrous

Answer 6

frequency of GnRH pulses increases gradually with the positive feedback of estradiol in the surge centre, leading to a surge in GnRH

pattern of LH secretions follows the pattern of GnRH secretion, and a surge in LH secretion also occurs

the preovulatory surge of LH causes ovulation of large dominant follicles

in some species, suckling or the presence of offspring causes the brain to release opioids in the brain that negatively affect secretion of GnRH