Issue 105 Item 9 Metformin Increases Fertility in PCOS Patients

In patients with polycystic ovary syndrome (PCOS), treatment with metformin alone or in combination with clomiphene citrate results in a substantial number of pregnancies, according to a report in the April issue of Fertility and Sterility. Dr. John E. Buster and colleagues, from Baylor College of Medicine, Houston, treated 49 anovulatory infertility patients diagnosed with PCOS with metformin. The patients received 500 mg metformin b.i.d. for 6 weeks. If by 6 weeks ovulation had not occurred, the dose was increased to 500 mg t.i.d. If no ovulatory response was observed after an additional 6 weeks, 50 mg clomiphene citrate was added. One patient dropped out of the trial because of side effects.

Nineteen patients (40%) resumed spontaneous menses and showed evidence of ovulation after treatment with metformin alone. Fifteen patients (31%) required additional therapy with clomiphene citrate. Of these, 10 (67%) had evidence of ovulation.

The investigators report that 20 patients (42%) conceived with a median time to conception of 3 months. Of these, seven (35%) had spontaneous abortions. Gastrointestinal-related side effects were observed in 19 patients (39%). Five patients (10%) reduced the dosage of metformin due to side effects.

"Reproductive efficiency with metformin may be superior to traditional therapy with clomiphene citrate but needs to be further tested in comparative trials," Dr. Buster and colleagues conclude.

Fertil Steril 2002;77:669-673.