Objective: To evaluate the effect of N-acetyl-cysteine (NAC), a mucolytic drug with insulin sensitizing properties, as an adjuvant therapy in subjects with polycystic ovary syndrome (PCOS) resistant to clomiphene citrate (CC).
Design: Placebo-controlled, double-blind randomized trial.
Setting: University-based hospital and private infertility practice.
Patient(s): One hundred fifty women diagnosed with CC-resistant PCOS, aged 18-39 years undergoing therapy for infertility were included.
Intervention(s): The patients were assigned randomly to receive either NAC 1.2 g/d (group I) or placebo (group II) with CC 100 mg/d for 5 days starting at day 3 of the cycle.
Main outcome measure(s): Ovulation rate and pregnancy rate (PR).
Result(s): Combination of CC and NAC significantly increased both ovulation rate and PR in women with CC-resistant PCOS (49.3% vs. 1.3% and 21.3% vs. 0%, respectively). No cases of ovarian hyperstimulation syndrome (OHSS) were reported in the NAC group; two cases of miscarriage (12.5%) were reported.
Conclusion(s): The NAC as an adjuvant to CC was more effective than placebo for CC-resistant patients with PCOS. It is safe and well tolerated.