Effect of Letrozole and Clomiphene Citrate versus Letrozole Alone for Ovulation Induction in Women with Polycystic Ovary Syndrome
Authors: Nazneen Sohely , Banu Jesmin , Ishrat Shakeela , Deeba Farzana , Rani Chalontika , Jahan Shirin , Akter Sumaiya , Debnath Mitu 
Published: September 2023

Background: Polycystic ovary syndrome (PCOS) is a common endocrinopathy characterized by oligo-ovulation or anovulation signs of androgen excess and multiple small ovarian cysts. It is thought to be one of the leading causes of female sub-fertility. It has been estimated that PCOS affects 5-10% of females in reproductive age. In this study, we used combination of letrozole and clomiphene vs letrozole alone in ovulation induction in infertile PCOS women. Objective: The objective of the study was to compare the effectiveness of the combination of letrozole and clomiphene citrate and letrozole alone in ovulation induction in infertile women with PCOS. Methods: Randomized controlled trial conducted in the Department of Reproductive Endocrinology and Infertility, Bangabandhu Sheikh Mujib Medical University, Dhaka, from July 2020 to June 2021. A total of 50 women 18-40 years of age with a diagnosis of infertility and PCOS as defined by the Rotterdam criteria and no other known cause of infertility were included in this study. Participants were randomly assigned into two groups by using a computer-generated random table to either 5 mg letrozole alone or the combination of 2.5 mg letrozole and 50 mg CC daily on cycle days 3-7 for two treatment cycle. Statistical analysis was performed by the SPSS program for Windows, version 22.0. Main outcome measured by number & size of mature follicles, endometrial thickness, day 21 serum progesterone & ovulation rate in both groups. The secondary outcome includes pregnancy rate and complication of both treatment arms. Results: Regarding demographic criteria, there was no significant difference between two groups. In the current study, clinical characteristics, laboratory parameters and cycle characteristics were also comparable to both groups and showed no significant difference. Dominant follicles were found 24(52.2%) in group A (CC+Letrozole) and 29(63.0%) in group B (Letrozole Alone) without any significant difference. Mono follicular development was found 18(75.0%) in group A and 24(82.8%) in group B which was not statistically significant. Endometrial thickness and serum progesterone level at 1st and 2nd cycle were not statistically significant between two groups (p>0.05). Ovulation rate was higher in group B than group A (76.0% vs 72.0%) with absolute difference 4.0 and relative ratio 0.95. Pregnancy rate was also higher in group B than group A (24.0% vs 16.0%) with absolute difference 8.0 and relative ratio 0.67. Ovulation and pregnancy rate were not statistically significant between two groups. Regarding side effects, no significant difference was found between two groups. Conclusion: Although it was not statistically significant, ovulation and pregnancy rate was a little higher in alone letrozole group than combined group. The results of this preliminary study suggested that letrozole may have a better role as a first-line treatment for anovulatory patients with PCOS.