Efficacy of an Extended 10-day Letrozole Regimen Compared to the 5-day Regimen in Enhancing Ovulation in Infertile Women with Polycystic Ovary Syndrome: A Randomised Controlled Trial

Background: Polycystic ovary syndrome (PCOS) is a leading cause of anovulatory infertility. Letrozole is the first-line agent for ovulation induction; however, response to the standard 5-day regimen may be suboptimal in some women. Aim: The aim is to compare the efficacy and safety of an extended 10-day letrozole regimen with the conventional 5-day regimen for ovulation induction in infertile women with PCOS. Settings and Design: Prospective, open-label, parallel-group randomised controlled trial conducted at a tertiary care centre in North India. Materials and Methods: Eighty infertile women with PCOS (Rotterdam criteria, 2003) were randomised to receive either letrozole 2.5 mg daily for 10 days or 5 days. Up to three ovulation induction cycles were allowed. Follicular monitoring was performed using transvaginal ultrasonography. Ovulation was triggered with human chorionic gonadotropin, followed by timed intercourse. Statistical Analysis Used: Continuous variables were analysed using the t -test or Wilcoxon–Mann–Whitney U test. Categorical variables were compared using the Chi-square or Fisher’s exact test. A P < 0.05 was considered statistically significant. Results: The 10-day regimen showed a significantly higher follicular response in the first cycle compared to the 5-day regimen (85.0% vs. 52.5%, P = 0.002). Dose escalation and gonadotropin use were significantly lower in the extended regimen group. No cases of ovarian hyperstimulation syndrome were reported. Pregnancy rates were comparable between groups. Conclusion: The extended 10-day letrozole regimen significantly improves follicular response without increasing adverse outcomes and may improve cycle efficiency in women with PCOS.