Twenty-four studies were evaluated to investigate the use of pharmacological therapy for women with gestational diabetes mellitus (GDM). In conjunction with nutrition therapy, pharmacological therapy is indicated in women with gestational diabetes mellitus when optimal blood glucose levels have not been maintained and/or when the rate of fetal growth is excessive. 

Insulin therapy has been shown to be safe and effective in maintaining optimal blood glucose levels and reducing incidence of macrosomia, fetal morbidity and mortality. Five studies regarding the use of insulin analogs reported that lispro or aspart as rapid acting insulins may improve glycemic control and reduce the incidence of macrosomia in neonates. Research on glargine is limited. 

Eight studies reported that glyburide therapy is effective in maintaining glycemic control in conjunction with nutrition therapy, especially in women with less severe disease. Research on metformin is limited.  Further research on other antidiabetes agents in women with gestational diabetes mellitus is needed.   

• Grade I means there is Good/Strong evidence supporting the statement;
• Grade II is Fair;
• Grade III is Limited/Weak;
• Grade IV is Expert Opinion Only;
• Grade V is Not Assignable.
• High (A) means we are very confident that the true effect lies close to that of the estimate of the effect;
• Moderate (B) means we are moderately confident in the effect estimate;
• Low (C) means our confidence in the effect estimate is limited;
• Very Low (D) means we have very little confidence in the effect estimate.
• Ungraded means a grade is not assignable.