Tamoxifen Versus Clomiphene Citrate for Ovulation Induction in Women with Polycystic Ovary Syndrome: A Prospective Randomized Trial

Abstract

OBJECTIVE: To evaluate the efficacy of induction of ovulation with tamoxifen (TMX) versus clomiphene citrate (CC) in anovulatory women with polycystic ovary syn- drome (PCOS) in a randomized controlled trial. STUDY DESIGN: The prospective, randomized, controlled study of 88 anovulatory women (193 cycles) with PCOS was undertaken. TMX oral tablets and CC oral tablets were started on day 5 of the menstrual cycle; 20 mg was given daily for 5 consecutive days for the TMX group (n=42) and 50 mg for the CC group (n=46). Primary outcomes were endometrial thickness, serum estradiol (E2) values, ovulation, clinical pregnancy, and live birth rates. Secondary outcomes were follicular development and miscarriage rates. RESULTS: Ovulation and pregnancy rates, respectively, were 71% and 23.8% (TMX group) and 74% and 19.6% (CC group) (differences not statistically significant). Mean endometrial thickness was significantly greater in the TMX group (p<0.01). The number of stimulated follicles between 12–18 mm in diameter was significantly greater in the CC group than in the TMX group (p<0.01). E2 values in the CC group were statistically significantly higher than in the TMX group. There was no difference in terms of miscarriage rates between the 2 groups. One twin pregnancy was detected in the CC group. CONCLUSION: TMX is not superior to CC but is as effective as CC for ovulation induction in women with PCOS. However, future randomized prospective studies with larger groups are needed to compare TMX and CC for ovulation induction in anovulatory infertile women with PCOS who had a thin endometrium (<7 mm). © Journal of Reproductive Medicine®, Inc.