Objective: To determine the effect of metformin pretreatment on in vitro maturation (IVM) in the patients with clomiphene citrate-resistant polycystic ovary syndrome.
Design: Prospective randomized study.
Setting: University affiliated hospital.
Patient(s): Fifty-six women with clomiphene citrate-resistant polycystic ovary syndrome underwent 70 cycles of IVM treatment.
Intervention(s): Metformin was administered at a dose of 500 mg twice per day for 12 weeks before IVM treatment.
Main outcome measure(s): The number of immature oocytes, oocyte maturation, fertilization, cleavage, high-quality embryo, and clinical pregnancy rates.
Result(s): A significantly higher high-quality embryo rate (37.8%) was obtained in the metformin-treated group compared with the control group (24.3%). Accordingly, the clinical pregnancy and implantation rates were significantly higher in the metformin-treated group (38.2% and 15.3%) than the control group (16.7% and 6.2%).
Conclusion(s): Pretreatment with metformin improves IVM outcome in terms of embryo quality and clinical pregnancy rate as well as implantation rate.