Comparison of Diet, Metformin and Insulin in the Treatment of Gestational Diabetes Mellitus

Objective: The aim of the study was to compare maternal and neonatal outcomes in patients with gestational diabetes mellitus (GDM) treated with metformin versus those with insulin, or diet alone.
Material and methods: The study included 24 GDM women treated with metformin, 21 treated with insulin, and 17 women only on diet. All patients were from Outpatient Department of Endocrinology in the period from May, 2008 to October, 2010.
Results: The three groups were comparable with respect to age, pre-pregnancy body mass index (BMI), weight gain during pregnancy, gestational week at enrolment, smoking cigarettes and positive family history for diabetes. Mean glycosylated haemoglobin (HbA1c) at 37 gestation week was lower in diet and metformin groups than insulin group (4,5±0,9, 5,3±0,7, and 6,1± 1,3 %, respectively, p< 0,01). Postprandial glycaemia (PPG) statistically significant differed in diet from metformin group (6,2±2,1 v.s. 7,5±1,1 mmol/L, p< 0,05) and in diet as to insulin group (6,2±2,1 v.s. 8,3±2,3 mmol/L, p< 0,01). There were statistically significant difference in mean gestational age at delivery, between the three (diet, metformin and insulin) groups (39,1±2,2; 38,7±1,6 and 37,3±2,4 gestation week, respectively, p< 0,05). The incidence of neonatal hypoglycemia was higher in the insulin group (52,4%) than in the metformin (33,3%) and diet group (17,6%), but there was statistically difference between insulin and diet group (p=0,04). No differences between the groups were observed in mode of delivery, birth weight, and incidence for large or small for gestational age.
Conclusion: Metformin is effective, easy and safe in controlling GDM.
Author Keywords: Gestational diabetes mellitus, metformin, insulin, glycaemia.