N-Acetyl cysteine and clomiphene citrate for induction of ovulation in polycystic ovary syndrome:: a cross-over trial

Objective. To compare clomiphene citrate plus N-acetyl cysteine versus clomiphene citrate for inducing ovulation in patients with polycystic ovary syndrome. Design. Prospective cross-over trial. Setting. University teaching hospital and a private practice setting. Patients. Five hundred and seventy-three patients were treated with clomiphene citrate for one menstrual cycle among which 470 patients were treated with clomiphene citrate plus N-acetyl cysteine for another cycle. All women suffered from polycystic ovary syndrome. Interventions. Patients had clomiphene citrate 50-mg tablets twice daily alone or with N-acetyl cysteine 1,200 mg/day orally for 5 days starting on day 3 of the menstrual cycle. Outcome measures. Primary outcomes were number of mature follicles, serum E2, serum progesterone, and endometrial thickness. Secondary outcome was the occurrence of pregnancy. Results. Ovulation rate improved significantly after the addition of N-acetyl cysteine (17.9% versus 52.1%). Although the number of mature follicles was more in the N-acetyl cysteine group (2.1 +/- 0.88 versus 3.2 +/- 0.93), the difference was not statistically significant. The mean E2 levels (pg/ml) at the time of human chorionic gonadotropine injection, serum progesterone levels (ng/ml) on days 21-23 of the cycle, and the endometrial thickness were significantly improved in the N-acetyl cysteine group. The overall pregnancy rate was 11.5% in the N-acetyl cysteine group. Insulin resistance occurred in 260 patients (55.4%). There was no significant difference between the insulin resistance group (n = 260) and non-insulin resistance group (n = 2 10) as regards ovulation rate, number of follicles, serum E2 (pg/ml), serum progesterone (ng/ml), endometrial thickness (mm), or pregnancy rate. Conclusion. N-Acetyl cysteine is proved effective in inducing or augmenting ovulation in polycystic ovary patients.