Effect of metformin treatment during pregnancy on women with PCOS: a systematic review and meta-analysis.

PURPOSE: Some previous studies have found that continued metformin use is beneficial in the management of polycystic ovary syndrome (PCOS) in pregnant women. A systemic review and meta-analysis were needed to more fully assess the effects of metformin on pregnant PCOS patients.

METHODS: The literature was fully searched using MEDLINE, EMBASE, SCOPUS, and COCHRANE for continued metformin use during pregnancy in women with PCOS. A systematic review and meta-analysis were performed to evaluate the comprehensive effects of continued metformin treatment on pregnancy-related outcomes in these women.

RESULTS: Eleven eligible studies out of 127 relevant publications were included in meta-analysis. The rates of early pregnancy loss and preterm delivery were found to be significantly decreased in metformin-treated PCOS women. A non-significant difference was found in fetal abnormality and fetal birth weight between the metformin-treated and the non-treated groups. The incidence of gestational diabetes mellitus (GDM) and hypertension/preeclampsia were not significantly different in the two groups, probably because of inconsistent results in the subgroup analysis.

CONCLUSIONS: Our results showed that continued use during of metformin, during pregnancy in women with PCOS, had no effect on incidence of fetal abnormalities or fetal birth weight. The effects of metformin on GDM and hypertension/preeclampsia should be determined through high-quality randomized controlled trials.