N-Acetylcysteine as an Adjuvant to Letrozole for Induction of Ovulation in Infertile Patients with Polycystic Ovary Syndrome


Department of Obstetrics and Gynecology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran


Background: This study was aimed to evaluate the influence of oral N-acetylcysteine (NAC) application as an adjuvant to letrozole on induced ovulation outcomes in patients with polycystic ovary syndrome (PCOS). Materials and Methods: This was a placebo-controlled double-blind randomized clinical trial with 130 PCOS patients who were infertile. First, patients were randomly divided into two groups. Patients in Group 1 were administered letrozole 5 mg/d plus NAC 1.2 g/d and patients in Group 2 were administered letrozole plus placebo for 5 days starting at the 3rd day of the menstruation period. On the 12th day of the cycle, ultrasound evaluation was performed, and in whom at least one follicle with an 18–20 mm diameter was found, 10,000 unit human chorionic gonadotropin (hCG) was prescribed, and 36 h after hCG injection, timed intercourse was advised. On the 16th day, after hCG injection, serum β-hCG level was evaluated. Results: The number of follicles >18 mm was significantly higher in the letrozole + NAC group (P = 0.007). The ovulation and pregnancy rates were also significantly higher in the letrozole + NAC group (P = 0.045). No adverse side effects and no cases of ovarian hyperstimulation syndrome were observed in NAC group. Conclusion: NAC is demonstrated to be a safe and well-tolerated adjuvant to letrozole and can increase the pregnancy rates in PCOS patients.


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