The following is an outline of practice guidelines for management of gestational diabetes mellitus. A detailed management plan and accompanying DecisionPaths can be found in the original guidelines:
Screening
Screen between the 24th and 28th gestational weeks; with any risk factor, consider screening at first prenatal visit.
Screen with 50-gram glucose challenge test: 1-hour plasma glucose >140 mg/dL positive; >120 mg/dL suspected.
Risk Factors
- Body mass index >25 kg/m2 (especially waist-to-hip ratio >1)
- Family history of type 2 diabetes (especially first-degree relatives)
- Age older than 25 years
- Multiparity
- Previous gestational diabetes: Macrosomic or large-for-gestational age infant (e.g., >9 lbs. or 4000 grams)
- Previous impaired fasting glucose with fasting plasma glucose 110 to 125 mg/dL
- Previous impaired glucose tolerance with oral glucose tolerance test 2-hour glucose value 140 to 199 mg/dL
- American Indian or Alaska Native, African American, Asian, Hispanic, Pacific Islander
Diagnosis
Plasma Glucose
100 gram oral glucose tolerance test after 8 to 10 hours overnight fast:
Fasting >95 mg/dL, 1 hour >180 mg/dL, 2 hour >155 mg/dL, 3 hour >140 mg/dL; two abnormal values required for diagnosis; if one abnormal, consider self-monitored blood glucose for 7 days; if average fasting blood glucose >95 mg/dL or average 2-hour post-meal >120 mg/dL, re-evaluate for gestational diabetes mellitus. See "Gestational: Master DecisionPath" in the full-text guideline.
Symptoms
Usually none. Rarely, increased urination, thirst, and appetite; nocturia; weight loss
Urine Ketones
Usually negative; positive can indicate starvation ketosis
Treatment Options
Medical nutrition therapy; Glyburide Stage; insulin Stages 3, 4
Targets
Self-Monitored Blood Glucose
- All values within target range
- Pre-meal and bedtime: 60 to 95 mg/dL
- Post-meal: <120 mg/dL 2 hours after start of meal; <140 mg/dL 1 hour after start of meal
Hemoglobin A1c(HbA1c)
May be used to evaluate prior hyperglycemia, but is not used in gestational diabetes management; should be within normal range
Urine Ketones (Fasting)
Negative
Monitoring
Self-Monitored Blood Glucose
6 to 7 times/day; before and 1 to 2 hours after start of meals, and at bedtime; 4 times/day minimum; fasting and 1 to 2 hours after start of meals
Method
Meter with memory and log book
Urine Ketones (Fasting)
Every morning until negative for 7 days, then every other morning
Follow-Up
Pre-natal
Phone 1 to 2 times a week to review self-monitored blood glucose data; office visit every 2 weeks up to 36 weeks, then weekly; self-monitored blood glucose data (download and check meter); frequency of hypoglycemia; weight or body mass index; medications; blood pressure; medical nutrition therapy; exercise
Fetal Monitoring
Kick counts at 28 weeks; non-stress test at 34 weeks and until end of pregnancy
After Delivery
In hospital: Check fasting blood glucose and 2 hours after breakfast each day.
After discharge: Check fasting blood glucose and blood glucose 2 hours after breakfast 1 day/week until first postpartum visit. If fasting blood glucose >120 mg/dL, and/or post-prandial blood glucose >160 mg/dL, evaluate for diabetes immediately.
6 weeks: Nutrition education if needed
3 to 6 months: Evaluate for diabetes and yearly thereafter
