No effect of a low dose of metformin on the lipid profile, body mass index and weight gain in pregnant women with obesity: A randomized trial.

Objective: Evaluate the lipid profile, Body Mass Index (BMI) and weight gain of pregnant women with obesity and the effect of a low dose (1000 mg/day) of metformin hydrochloride on these parameters.

Methods: A randomized clinical trial was performed from October 31th, 2014 to January 25th, 2018 with pregnant women diagnosed with obesity by arrival BMI ≥ 30.0 kg/m. The participants were randomized into two groups: metformin and control. All pregnant women received standard prenatal follow-up and the same instructions of diet and physical exercise. Laboratory tests were performed at three different times: first moment with gestational age (GA) < 20 weeks, second (GA 24-28 weeks) and third (GA 32-34 weeks) measuring maternal serum levels of total cholesterol (TC), low density lipoprotein (LDL), high density lipoprotein (HDL) and triglycerides (TG) as well as weight gain and BMI were monitored.

Results: A total of 424 pregnant women with obesity were evaluated. Of these, 218 (51.41%) composed the control group and 206 (48.59%) the metformin group. There was no difference of lipid profile, BMI and weight gain values between groups during the 1st, 2nd and 3rd evaluation moments. A significant difference was observed, only in the BMI, HDL and TG values from 1st to 3rd evaluation moments.

Conclusion: Low dose (1000 mg/day) of the drug showed no effect on the lipid profile, BMI and weight gain in pregnant women with obesity in metformin group during the evaluation moments.