Pregnancy and Parturition Flashcards
at the time of ovulation the oocyte is surrounded by the
zone pellucide + granulosa cells
the granulosa cells and theca cells eventually develop into the
corpus luteum
the oocyte remains fertile for about
6-24 hours
as the oocyte traverses through the oviduct the initial movement is
rapid
why is the initial movement rapid?
the contraction of myoepithelial cells
the contractions of myoepithelial cells are speeded by
estrogen
overall it takes how long fro the oocyte to travel through the oviduct?
4 days
where does fertilization take place?
the oviduct
capacitation means what?
when the sperm spends some time in the female reproductive tract
the sperm bind to what on the egg?
the zona pellucida
when the zygote reaches the uterus it has developed into a
blastocyte
the outer layer of cells of the zygote form the
placenta
there is a limited window to which the uterus is receptive to implantation, what 2 things are needed?
estrogen and progesterone
how many zygotes don’t even become blastocytes?
1/3-1/2
what % of blastocytes implant
70-75
how many implanted blastocytes survive to the second week?
1/2
how many blastocytes that survive the second week are spontaneously aborted?
16%
what are the 4 functions of the placenta?
gas exchange, nutrient-waste exchange, protective barrier and synthesizes and secretes hormones
the placenta secretes 7 hormones which are
hCG, estrogen, progesterone, hCS, GnRH, ACTH, relaxin
hCG secretion increases rapidly after
fertilization
estrogens and progestins are first produced by what? but then get produced by what?
the corpus luteum but after 6 weeks get produced by the placenta
estrogens and progestins continue to increase or decreases as pregnancy goes on?
increase
which hormone levels off toward the end of pregnancy? which hormone continues to increase?
progestins level off, estrogen increases
estrogens maintain 4 things
uterine endometrium
ductal proliferation
increasing the number of oxytocin receptor
increasing the number of gap junctions
progestins do 5 things
maintain secretory function of the endometrium
maintain the decidual cells
quiet the myometrium
developing the lobules and alveoli in the breasts
hCS is made by what?
syncytiotrophoblasts
hCS does 4 things
increases mammary cel proliferation
increases insulin secretion
increaes lipolysis
spares glucose for fetal use
PRL is essential for what 2 things
mammary development and lactation
the placenta secretes what 4 main hormones in response to pregnancy
estrogen, progesterone, chrorionic gonadotropin, placental lactogen
anterior pituitary secretes what 2 hormones a lot and what 2 hormones a little
a lot: PRL, ACTH
little: FSH, LH
adrenal cortex increases secretion of what 2 hormones?
aldosterone and cortisol
posterior pituitary increases secretion of what hormone
vasopressin
parathyroid increases secretion of what hormone?
PTH
kidney increases secretion of what hormones? (3)
renin, EPO, vit. d
what are the causes of increased kidney hormone secretions (3 things)
estrogen, progesterone, PRL
does blood volume increase or decrease when pregnant?
increase
