CLINICAL OUTCOMES OF LETROZOLE VERSUS CLOMIPHENE CITRATE IN OVULATION INDUCTION THERAPY
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Keywords
Letrozole, Clomiphene Citrate, Ovulation Induction, PCOS, Infertility.
Abstract
Clomiphene citrate has long been the standard treatment for ovulation induction in women with polycystic ovarian syndrome (PCOS); however, its antiestrogenic effects and resistance issues limit its efficacy. Letrozole, an aromatase inhibitor, has emerged as a promising alternative treatment. This study aimed to compare the clinical outcomes of letrozole versus clomiphene citrate in ovulation induction therapy among infertile women with PCOS in a Bangladeshi tertiary care setting.
Methods: This randomized controlled trial was conducted at the Department of Obstetrics and Gynaecology, Bangabandhu Sheikh Mujib Medical University, Dhaka, from January 2009 to December 2010. A total of 500 women (250 per group) with anovulatory infertility received either 2.5 mg letrozole or 50 mg Clomiphene citrate from days 2 to 6 of their menstrual cycle. The primary outcomes included ovulation rate, endometrial thickness, clinical pregnancy rate, and live birth rate. Results: Letrozole showed a significantly higher ovulation rate (76.8% vs. 61.2%, p=0.001), thicker endometrium (8.9 mm vs. 7.4 mm, p<0.001), and improved clinical pregnancy (29.2% vs. 19.6%, p=0.01) and live birth rates (24.8% vs. 16.0%, p=0.02) than Clomiphene citrate. Adverse effects were more common in the Clomiphene citrate group.
Conclusion: Letrozole is more effective and better tolerated than clomiphene citrate for ovulation induction and should be considered a first-line option for the treatment of anovulatory infertility in similar clinical settings.
References
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Humaira Alam
Assistant Professor, Department of Obstetrics and Gynaecology, Bangabandhu Sheikh Mujib Medical University, Dhaka, Bangladesh
Sayeba Akhter
Former Professor, Department of Obstetrics and Gynaecology, Bangabandhu Sheikh Mujib Medical University, Dhaka, Bangladesh
Nigar Sultana
Assistant Professor, Department of Obstetrics and Gynaecology, Bangabandhu Sheikh Mujib Medical University, Dhaka, Bangladesh
Kazi Farhana Begum
Medical Officer, Department of Obstetrics and Gynaecology, Bangabandhu Sheikh Mujib Medical University, Dhaka, Bangladesh