LETROZOLE VERSUS CLOMIPHENE CITRATE FOR OVULATION INDUCTION IN WOMEN WITH POLYCYSTIC OVARY SYNDROME

Abstract

Polycystic ovarian disease (PCOS) is a condition characterized by disruption of the regular process of ovulation. It is associated with hyperandrogenemia; normal or elevated estrogen level; raised LH secretion with alteration of normal relationship between LH and FSH leading to a raised LH/FSH ratio. The ovaries -are usually although not always enlarged and lobular. On histological examination the ovaries contain atretic follicles; theca cells hyperplasia and generalized increase in stroma. On ultrasound examination, the ovaries are characterized by peripheral distribution of multiple subcapsular cysts (necklace appearance). PCOS presents in many patients with hirsutism and obesity in addition to oligomenorrhea. Approximately 5-10% of women in general population have this syndrome but it is the cause in about 30% of women with infertility.

Inhibition of estrogen feedback at the level of hypothalamus- pituitary has been associated with a surge in FSH secretion. This surge in FSH secretion is associated with growth of Graafian follicle and an increase in estrogen secretion. When successful, the Graafian follicle continues to enlarge and eventually ruptures releasing an ovum i.e. ovulation. Approximately 80% of PCOS women treated with clomiphene citrate; ovulate and approximately 20%-40% become pregnant.

Clomiphene citrate is usually given in dose of 100mg daily for 5 days. Clomiphene citrate is associated with higher than normal incidence of multi-fetal pregnancy.