N-Acetylcysteine improves oocyte and embryo quality in polycystic ovary syndrome patients undergoing intracytoplasmic sperm injection: an alternative to metformin.

Polycystic ovary syndrome (PCOS) is associated with low-quality oocytes. The aim of the present study was to investigate the effects of metformin (MET), N-acetylcysteine (NAC) and their combination on follicular fluid parameters, oocytes and embryo quality in PCOS patients. A prospective randomised placebo-controlled pilot study on 60 Iranian women with PCOS (aged 25-35 years) undergoing intracytoplasmic sperm injection (ICSI) was designed. Women were divided into four groups (n=15 in each): (1) an MET, administered 1500mg day(-1) MET; (2) an NAC group, administered 1800mg day(-1) NAC; (3) an NAC + MET group; and (4) a placebo group. Drugs were administered from the 3rd day of previous cycle until the day of oocyte aspiration (6 weeks treatment in total). Data were analysed by one-way ANOVA, with significance set at P<0.05. The number of immature and abnormal oocytes decreased significantly in the NAC compared with placebo group, with a concomitant increase in the number of good-quality embryos in the NAC group (P<0.05). Malondialdehyde levels decreased significantly in the NAC and NAC + MET groups compared with the placebo-treated group (P<0.02). In addition, there were significant decreases in leptin levels in the NAC, MET and NAC + MET groups compared with the placebo group (P<0.001). Insulin and LH levels were significantly lower in the MET and NAC groups compared with the placebo-treated group (P<0.02). We concluded that NAC improves oocyte and embryo quality and could be administered as an alternative to MET.