Metformin - Old News? Does Metformin Prevent Miscarriages in PCOS Patients?

Aims: To present the available evidences that examine the role of metformin administration in the prevention of 1^st trimester miscarriages in PCOS patients.

Materials and Methods: A literature review was conducted for all relevant articles assessing the effect of metformin administration on the prevalence of 1^st trimester miscarriages in PCOS patients.

Results: PCOS patients demonstrate numerous clinical presentations with clinical heterogeneity as a rule. While insulin resistance is common in PCOS patients, both in obese and nonobese women, reports on the prevalence of insulin resistance vary depending on tests employed and the heterogeneity of PCOS. The majority of the available studies on the role of metformin in the prevention of 1^st trimester miscarriages are observational, uncontrolled, of short duration, and women were not necessarily selected or tested for hyperinsulinemia. Nevertheless, in the vast majority of studies, PCOS women with insulin resistance who received preconceptional metformin achieved a lower miscarriage rate.

Conclusions: The use of metformin in PCOS with glucose intolerance is associated with a tendency toward an improved pregnancy outcome, with no evidence of increased major malformations or neonatal death rates.