Am J Perinatol 2013; 30(06): 483-490
DOI: 10.1055/s-0032-1326994
Original Article
Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Metformin Compared with Insulin in the Treatment of Pregnant Women with Overt Diabetes: A Randomized Controlled Trial

M. Ashley Hickman
1   Division of Maternal Fetal Medicine, Department of Obstetrics and Gynecology, University of North Carolina, Chapel Hill, North Carolina
Ryan McBride
2   Department of Biostatistics; University of North Carolina, Chapel Hill, North Carolina
Kim A. Boggess
1   Division of Maternal Fetal Medicine, Department of Obstetrics and Gynecology, University of North Carolina, Chapel Hill, North Carolina
Robert Strauss
1   Division of Maternal Fetal Medicine, Department of Obstetrics and Gynecology, University of North Carolina, Chapel Hill, North Carolina
› Author Affiliations
Further Information

Publication History

31 May 2012

04 June 2012

Publication Date:
24 October 2012 (online)


Objective To compare the safety and tolerability of metformin to insulin for glycemic control among women with preexisting type 2 and early A2 gestational diabetes.

Study Design Women with preexisting type 2 diabetes and those diagnosed with gestational diabetes who required medical management prior to 20 weeks were randomly assigned to metformin or insulin. Glycemic control, defined as >50% capillary blood glucose within target range, was compared between groups. Other outcomes included patient tolerance, neonatal and obstetric complications, maternal weight gain, neonatal cord blood C-peptide, and patient satisfaction with therapy.

Results Twenty-eight women completed the study, with 14 in each group. Of the 15 women assigned to metformin, 100% continued to receive metformin until delivery, although 43% required supplemental insulin to achieve glycemic control. Glucose measures did not differ between the groups, and the proportion who met fasting and postprandial glycemic target values did not differ between the groups. Women treated with metformin had significantly fewer subjective episodes of hypoglycemia compared with those using insulin (0% versus 36%; p = 0.04) as well as reported glucose values < 60 mg/dL (7.1% versus 50%; p = 0.03).

Conclusion Metformin should be considered for treatment of overt diabetes and early A2 gestational diabetes in pregnancy.

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