Gestational Diabetes Mellitus
Recommendations and Conclusions
The following recommendations and conclusions are based on good and consistent scientific evidence.
- Women in whom GDM is diagnosed should receive nutrition and exercise counseling, and when this fails to adequately control glucose levels, medication should be used for maternal and fetal benefit.
- When pharmacologic treatment of GDM is indicated, insulin is considered the preferred treatment for diabetes in pregnancy.
The following recommendations and conclusions are based on limited or inconsistent scientific evidence.
- All pregnant women should be screened for GDM with a laboratory-based screening test(s) using blood glucose levels.
- In women who decline insulin therapy or who the obstetricians or other obstetric care providers believe will be unable to safely administer insulin, or for women who cannot afford insulin, metformin is a reasonable alternative choice.
- Glyburide treatment should not be recommended as a first-choice pharmacologic treatment because, in most studies, it does not yield equivalent outcomes to insulin.
- Health care providers should counsel women of the limitations in safety data when prescribing oral agents to women with GDM.
The following recommendations and conclusions are based primarily on consensus and expert opinion.
- In the absence of clear evidence that supports one cutoff value over another (ie, 130 mg/dL, 135 mg/ dL, or 140 mg/dL) for the 1-hour glucose screening test, obstetricians and obstetric care providers may select one of these as a single consistent cutoff for their practice, using factors such as community prev- alence rates of GDM when making their decision.
- In the absence of clear comparative trials, one set of diagnostic criteria for the 3-hour OGTT cannot be clearly recommended over the other. Given the ben- efits of standardization, practitioners and institutions should select a single set of diagnostic criteria, either plasma or serum glucose levels designated by the Carpenter and Coustan criteria or the plasma levels established by the National Diabetes Data Group, for consistent use within their patient populations.
- Once a woman with GDM begins nutrition therapy (dietary counseling), surveillance of blood glucose levels is required to confirm that glycemic control has been established.
- In practice, three meals and two to three snacks are recommended to distribute carbohydrate intake and to reduce postprandial glucose fluctuations.
- Women with GDM should aim for 30 minutes of moderate-intensity aerobic exercise at least 5 days a week or a minimum of 150 minutes per week.
- The timing of delivery in women with GDM that is controlled with only diet and exercise (A1GDM) should not be before 39 weeks of gestation, unless otherwise indicated. In such women, expectant management up to 40 6/7 weeks of gestation in the setting of indicated antepartum testing is general- ly appropriate.
- For women with GDM that is well controlled by medications (A2GDM), delivery is recommended at 39 0/7 to 39 6/7 weeks of gestation.
- Screening at 4–12 weeks postpartum is recommend- ed for all women who had GDM to identify women with diabetes, impaired fasting glucose levels, or impaired glucose tolerance. Women with impaired fasting glucose, IGT, or diabetes should be referred for preventive or medical therapy. The ADA and ACOG recommend repeat testing every 1–3 years for women who had a pregnancy affected by GDM and normal postpartum screening test results.
- Women with GDM should be counseled regarding the risks and benefits of a scheduled cesarean deliv- ery when the estimated fetal weight is 4,500 g or more.
Gestational Diabetes Mellitus
February 1, 2018
External Publication Status
Country of Publication
Female, Adolescent, Adult
Health Care Settings
Physician, nurse midwife, nurse, dietician nutritionist, diabetes educator
Diagnosis, Management, Treatment
D016640 - Diabetes, Gestational
gestational diabetes, GDM, gestational diabetes mellitus