The role of continuing metformin therapy during pregnancy in the reduction of gestational diabetes and improving pregnancy outcomes in women with polycystic ovary syndrome

Objectives

To evaluate the value of continuing metformin therapy in women with PCOS throughout pregnancy and its role in reducing the development of gestational diabetes and improving pregnancy outcome by reducing spontaneous miscarriage rate.

Study design

Non randomized, controlled clinical trial.

Population

Fifty-seven infertile cases with polycystic ovary syndrome who became pregnant were classified into two groups: group 1 included 31 cases who conceived while taking metformin therapy with or without other ovulation inducing agents and continued metformin during pregnancy in a dose of 1000–1500 mg daily and group 2 included 26 cases who conceived without taking metformin and did not take it during pregnancy.

Outcome measures

Maternal outcome measures including; assessment of insulin resistance, incidence of gestational diabetes mellitus, the need for insulin therapy and incidence of preeclampsia. Fetal outcome measures include incidence of, spontaneous miscarriage, preterm birth, fetal growth abnormalities, suspected fetal asphyxia at birth, fetal anomalies and neonatal mortality.

Results

The incidence of gestational diabetes mellitus was significantly lower in cases who received metformin than those who did not receive metformin during pregnancy (3.2% versus 23.08%, respectively), and spontaneous miscarriage occurred in one case (3.2%) in patients who continued metformin compared to 7 cases (26.9%) in patients who did not take metformin. No significant differences between both groups in other outcome measures.

Conclusion

Continuous metformin therapy throughout pregnancy in women with PCOS improves pregnancy outcomes by decreasing spontaneous miscarriage rates and prevention of gestational diabetes mellitus with its co morbidity and mortality.