Endocrinology of OBGYN Flashcards
(24 cards)
What reproductive hormones are secreted by the Hypothalamus, Ant Pit and Ovary?
Hyp: GnRH
AP: LH, FSH
Ovary: Estrogen, Progest, Inhibins
WHat are the two phases of the ovarian cylce?
Follicular and Luteal Phase?
What happens during the follicular phase?
-follicle Devt
-Endometrial prolif.
-Ovulation
ESTROGEN SYNTHESIS
What happens during the Luteal phase?
Corpus Luteum forms
Endometrial Diff
Menses
How are GnRH, FSH and LH secreted?
Pulsatile fashion
What hormonal changes occurr at ovulation?
Spike in FSH and LH
What homrone is predominant in the Follicular Phase? Luteal Phase?
Estrogen
Progesterone > Estrogen
What causes the Surge of hormones at midcylce?
Change from negative feedback to positive feedback at midpoint. Back to neg feedback in luteal phase.
What are the cell types involved in Estrogen production during the Follicular phase?
Theca cells: LH Recept => Androstendione => GC and circ
Granulosa Cell: FSH Recept => Estradiol => Circ
WHat happens to the Theca Cells and Granulosa cells during the Follicular Phase?
Increase in numbers of cells and increase in sensitivity of cells to hormone
What is the action of Inhibin B?
Causes the decline of FSH
What hormone causes the rupture of the follacle?
LH (required for ovulation)
What changes in the THeca/Granulosa Cells in the Luteal Phase?
BOTH have LH/hCG recpetors
Theca-lutein cell produces Androstendione =>
Granulosa-lutein cell produces Estradiol AND PROGESTERONE (increae in Cholesterol uptake to synth progesterone)
How is Negative feedback mediated during the Luteal phase?
Rise in progesterone and Inhibin A exerts neg feedback at the level of the Ant Pit
Gonadotropin production declines => dec steroid prod
What are rhe fetal components of the placenta?
Syncytiotrophoblasts
Cytotrophoblasts
Mesenchyme
Fetal BV
What are rhe maternal components of the placenta?
Decidual cells
Maternal Arteries and veins
How is oxygen exchanged from mother to Fetus?
Gas exchange occurrs at the placenta
What key hormones are produced by the placenta?
hCG Hyman placental lactogen (hPL) CRH Progesterone Estrogens
What key hormones are produced by the fetus during pregnancy?
Dehydroepiandrosterone (DHEA)
What key hormones are produced by the mother during pregnancy?
Progesterone
DHEA
Estrogens
What is the role of hCG during Pregnancy?
Bind LH receptors
Maint corpus luteum
Maint ovarian steroid production
What is the role of hPL during Pregnancy?
Fetal Metabolism
Fetal Growth and Devt
Stim prod of IGF, insulin, Adrenocortical hormones, surfactant
What is the role of CRH during pregnancy?
Onset of labor
Prostaglandin prod
Maint bloodflow in placenta
What is the role of Progesterone and 17-hydroxyprogesterone during pregnancy?
Inhibits prostaglandin prod
Supresses uterine contractions
Modulate immune response.
