Postpartum Care for Women with Gestational Diabetes Mellitus

Screening and Diagnosis

Women with a history of gestational diabetes mellitus (GDM) should be screened at 4-12 weeks postpartum using a 75-g oral glucose tolerance test (OGTT) with non-pregnancy diagnostic criteria, followed by lifelong screening for diabetes every 1-3 years, as recommended by the American Diabetes Association 1
A 75-g OGTT is the recommended screening test at 4-12 weeks postpartum, as it provides a more accurate diagnosis than HbA1c, which may be affected by pregnancy-related changes in red blood cell turnover and postpartum blood loss 1
Diagnostic criteria for the 75-g OGTT include: Fasting plasma glucose ≥126 mg/dL or 2-h plasma glucose ≥200 mg/dL, and if only one abnormal value meets diabetes criteria, the test should be repeated to confirm 1
The American Diabetes Association defines an abnormal OGCT as a 1-hour glucose level of 140 mg/dL (7.8 mmol/L) or higher 2, 3
GDM is diagnosed when two or more values meet or exceed the following thresholds on a diagnostic 100-gram OGTT:
Time Threshold
Fasting ≥95 mg/dL
1-hour ≥180 mg/dL
2-hour ≥155 mg/dL
3-hour ≥140 mg/dL
The 75-gram OGTT can be performed directly at 24-28 weeks gestation, requiring fasting, with blood glucose measured at fasting, 1-hour, and 2-hour after consuming 75g glucose, and GDM diagnosed when any one value meets or exceeds thresholds:
Time Threshold
Fasting ≥92 mg/dL
1-hour ≥180 mg/dL
2-hour ≥153 mg/dL

Women with GDM have a 50-60% lifetime risk of developing type 2 diabetes, with the risk of progression increasing linearly over time 1, 8, 5
Women with GDM have a 10-fold increased risk of developing type 2 diabetes later in life, as reported by the American Diabetes Association 9
The risk of developing type 2 diabetes can be delayed or prevented with intensive lifestyle interventions and/or metformin, particularly in women with overweight/obesity and a history of GDM who develop prediabetes 1

Intensive lifestyle interventions and/or metformin should be offered to women with overweight/obesity and a history of GDM who develop prediabetes, as shown in the Diabetes Prevention Program 1
Breastfeeding is recommended to reduce the risk of maternal type 2 diabetes 1
Preconception screening for diabetes should be sought before future pregnancies, and postpartum care should include psychosocial assessment and support for self-care 1
Women with GDM should perform fasting and postprandial blood glucose monitoring, with target glucose values of fasting <95 mg/dL, 1-hour postprandial <140 mg/dL, and 2-hour postprandial <120 mg/dL, as recommended by the American College of Physicians and American Diabetes Association 10, 11, 12
First-line treatment includes lifestyle modifications, such as moderate physical activity and dietary modifications, and second-line treatment includes insulin therapy when lifestyle modifications fail to maintain target glucose levels, as recommended by the American College of Physicians and American College of Obstetricians and Gynecologists 2, 11, 12

Many women are lost to follow-up after the initial postpartum period, despite their high lifetime risk of developing type 2 diabetes, highlighting the need for long-term follow-up and prevention strategies 1
Women with prediabetes after GDM benefit significantly from lifestyle interventions and/or metformin, but these interventions are often not implemented, missing opportunities for diabetes prevention 1
Lifelong screening for diabetes should occur at least every 3 years, according to the American Diabetes Association 5, 13, 1, 8

The prevalence of GDM ranges from 1-14% depending on the population studied, according to the American Diabetes Association 2
Treatment of gestational diabetes reduces the risk of preeclampsia, macrosomia, and shoulder dystocia, according to the American Family Physician and American College of Physicians 14, 11