True about clomiphene citrate :

Clomiphene Citrate : It is a non-steroidal triphenylethylene derivative Selective estrogen receptor modulator with both estrogen agonist and antagonist propeies Racemic mixture of two stereoisomers Enclomiphene (trans): 62% Zuclomiphene (cis): 38%, responsible for ovulation Mechanism of action: It is structurally similar to estrogen Competes for nuclear estrogen receptors throughout reproductive system At hypothalamic level it prevents accurate interpretation of estrogen levels Reduces negative feedback of estrogen triggering normal hypothalamic pituitary ovarian axis. Hence it allows the release of GnRH into the pitutary poal system and stimulates LH and FSH secetion. It has antiestrogenic action at level of cervix and endometrium Indications: Anovulatory infeility, ovulation induction, male infeility due to defective spermatogenesis due to hypogonadism Chances of multiple pregnancy: Twins: 7-10% Higher order: 0.1-0.3% Pregnancy rate is about 50% compared to placebo Ref: D.C. Dutta's Textbook of Gynaecology, 6th edition, page no: 533