Metformin versus insulin treatment in gestational diabetes in pregnancy in a developing country. A randomized control trial

.•A randomized control trial was conducted in two hospitals from two districts of Karachi, comparing metformin with insulin treatment in GDM.•Metformin exerted better effects on neonatal and maternal outcomes than on the glycemic profiles in women with GDM.•Less weight gain in pregnancy and lower rates of pre eclampsia was found in metformin treated patients with GDM.•Metformin with or without supplemental insulin is a cheap, cost effective treatment option for women with GDM.

AimTo compare treatment with metformin alone, metformin plus insulin and insulin alone in women with gestational diabetes (GDM).MethodA total of 150 gestational diabetic patients who fulfilled the eligibility criteria were included in this prospective randomized control open labeled study. A risk factor based screening was done followed by a GCT and then local GTT criteria from antenatal clinics. They were initially divided into two groups with odd numbers assigned to metformin treatment and even numbers to insulin treatment. Metformin and/or insulin treatment was given and target blood sugar levels aimed at FBS ≤ 100 mg/dl and postprandial levels ≤126 mg/dl. Supplemental insulin was added to metformin treatment group to maintain the glycemic targets if required. Patients were followed until delivery and maternal fetal outcomes and pharmacotherapeutic characteristics were recorded on a performa.ResultsLess maternal weight gain was found in the metformin treated groups (9.8 ± 1.5 kg [metformin alone] vs. 9.8 ± 1.4 kg [metformin plus insulin] vs. 12.5 ± 1.1 kg [insulin alone] P < 0.000). Preeclampsia was significantly less in metformin treated groups. There were no perinatal deaths in the study. Mean birth weight was significantly less in metformin treated groups (3.4 ± 0.4 kg vs. 3.3 ± 0.5 kg vs. 3.7 ± 0.5 kg P < 0.01). Less neonatal morbidity was observed in metformin groups. 42.7% of patients required supplemental insulin (mean dose of 13.6 ± 2 units) in the metformin group. Mean gestational age at which insulin was added was 31.8 ± 5.9 weeks.ConclusionMetformin is an effective and cheap treatment option for women with gestational diabetes with or without supplemental insulin.