Letrozole Therapy versus Extended Clomiphene Citrate Therapy for Induction of Ovulation in Resistant Patients with Polycystic Ovarian Syndrome in Low Resource Communities

Background: many drugs can be used in ovulation induction in patients with clomiphene-resistant polycystic ovarian syndrome (PCOs). Objective: to evaluate the effect of letrozole therapy versus extended clomiphene citrate therapy for ovulation induction in clomiphene-resistant polycystic ovarian syndrome patients Patients and Methods: The study included 100 infertile patients who had failed induction by clomiphene for three cycles. They were randomly allocated to receive either letrozole or extended clomiphene therapy. The effects of these drugs on follicular volume, ovulation, endometrium thickness and occurrence of pregnancy were evaluated. Results: No significant difference was found between both groups regarding age, body mass index, basal FSH level, LH level, prolactin level, thyroid function and semen analysis of the husband. Use of letrozole or extended clomiphene led to improvement of number of growing follicles, ovulation rate and pregnancy rate after 3 cycles of ovulation induction. Conclusion: The results of this study revealed that use of letrozole or extended treatment with clomiphene did not show better outcomes over each other in number of growing follicles, ovulation rates, occurrence of pregnancy and pregnancy outcomes. Letrozole group showed a significant increase in the endometrium thickness than extended clomiphene group but this did not affect pregnancy rate.