Current trends in the diagnosis and management of gestational diabetes mellitus in the United States

Objective: To assess current practice patterns among members of the Society for Maternal-Fetal Medicine (SMFM) with respect to the diagnosis and management of gestational diabetes mellitus (GDM). Methods: A 38 question survey on GDM diagnosis and management was distributed to SMFM members. Results: 2330 SMFM members were surveyed with a 40% response rate. Overall, 90.6% of respondents recommend a 2-step (versus a 1-step) diagnostic test. Cutoff values for the 1-h-50 g glucose challenge test vary from 130-140 mg/dL, but the majority (83%) adopts Carpenter Coustan criteria for the 3-h-100 g oral glucose tolerance test. The majority recommend glucose testing four times a day, with 55% preferring post-prandial testing at 2 h. Glyburide is used by 57% as a first-line agent, while 4% use metformin. Long-acting insulin analogs (glargine and/or detemir) are used by 46% and 33.6% of respondents, respectively. Antenatal testing is recommended by 38.7% for diet-controlled GDM compared to 98.7% for pharmacologically controlled GDM, with 56% starting by 34 weeks gestation. Most respondents recommend delivery of diet-controlled GDM at 40 weeks and pharmacologically controlled GDM at 39 weeks. Most (69%) offer elective cesarean section for an estimated fetal weight of 44500 g. Conclusions: There is significant variation in the diagnosis and management of GDM among SMFM members.