Describe the mechanisms of action of estrogen.
Hypothalamus: suppresses release of GnRH
Pituitary: suppresses release of gonadotropins
Decreased LH production and release leads to inhibition of ovulation.
Decreased FSH level prevents ovarian folliculogenesis.
Describe the mechanism of aciton of progestin.
synthetic progesterone
Inhibits GnRH and LH secretion and thus suppresses ovulation (main contraceptive mechanism)
Inhibits endometrial proliferation, thereby preventing the implantation of the embryo
Changes cervical mucus (↓ volume and ↑ viscosity) and impairs fallopian tube peristalsis, thereby inhibiting sperm ascension and egg implantation
Inhibits follicular maturation
Describe the mechanism of aciton of antiprogestin.
inhibition of the progesterone receptor causes inhibition or delay of ovulation, suppression of endometrial maturation, and pregnancy termination
Zuletzt geändertvor 2 Jahren