Gestational diabetes mellitus (GDM) is a state of impaired glucose tolerance recognized during pregnancy in women not known to have had impaired glucose tolerance before pregnancy.
The study involved 117 patients diagnosed with GDM with singleton pregnancies between 21 and 34 weeks of gestation, recruited between December 2012 and August 2015. 47 patients were controlled by diet and exercise.70 patients were given metformin in addition to lifestyle changes in a dose of 500- 2000 mg daily. Insulin was used when normo-glycemia was not achieved with the maximal daily dose of metformin in 2 weeks. 9 patients were given insulin after 4-6 days of metformin as they developed marked GIT upsets. Of the 61 patients who received metformin, 46 patients became controlled on metformin only. Metformin was comparable to insulin treatment as regard mean maternal fasting blood glucose (106.7 ±10.6 Vs 105.3 ±12.4), 2 hr pp blood glucose (123.3 ±15.4 Vs 124.1 ±13.8), glycosylated HbA1c before delivery (5.6±0.4 Vs 5.9±0.3) and the reduction in the HbA1c. The incidence of neonatal macrosomia at time of delivery was equal in both groups. So, we conclude that, in the short term, in women with gestational diabetes requiring drug treatment, metformin is comparable to insulin in glycemic control and neonatal outcomes.