Embedded Files
- 6-7% of pregnancies complicated by diabetes mellitus.
- The offspring of women with GDM are at increased risk of macrosomia, neonatal hypoglycemia, hyperbilirubinemia, operative delivery, shoulder dystocia, and birth trauma.
Screening & Diagnosis:
- 1hr 50g GTT at 24-28 weeks (threshold: 130-140 mg/dL)
- OR, early testing in: Previous medical history of GDM, Known impaired glucose metabolism, Obesity (BMI > or = 30)
- If GDM is not diagnosed, blood glucose testing should be repeated at 24–28 weeks of gestation.
- High 1 hr GTT, proceed to 3 hr (100g) GTT:
Carpenter and Coustan Thresholds:
Fasting: 95
1 hr: 180
2 hr: 155
3 hr : 140
(National Diabetes Date Group: 105, 190, 165, 145)
Antepartum:
- 4 times daily glucose testing: Fasting (90), and 1 (140) or 2 (120) hr postprandial.
- Diet: 3 meals and 2-3 snacks daily.
- Moderate exercise plan
- No specific ACOG recommendations for antepartum testing per Practice Bulletins.
Per UpToDate:
- US at 36-39 weeks for EFW. If poorly controlled, consider 28, 32, 36 week US.
- 2 weekly NSTs starting at 32 weeks for women requiring pharmacologic treatment for glycemic control (or, once weekly until 36 weeks, then twice weekly).
- No NSTs for euglycemic women on nutritional control, and delivery can wait until 41 weeks, unless otherwise indicated.
Insulin Dosing:
- AM dose = 2/3 daily dose
- 2/3 NPH and 1/3 regular or lispro before breakfast
(if on regular insulin, postprandial sugars should be checked at 2 hrs)
- PM dose = 1/3 daily dose
- 1/2 regular or lispro insulin before dinner and 1/2 NPH before bedtime.
OR...
- 1/2 daily dose - glargine (long acting - 24 hrs) (Start with less than 1/2 for long acting to avoid hypoglycemia)
- 1/2 daily dose - aspart split into 1/3 for each meal (short acting)
- Adjust dose in 10-20% increments.
- Carb counting
- early gestation-->1 unit insulin for every 15 g carbs
- later gestation-->1 unit insulin for every 10 g carbs
- 10 g carbs increases blood glucose by 300 mg/dL
- 1 unit short acting insulin lowers blood glucose by 30 mg/dL
- For pre-prandial blood sugar corrections, start with 20:1 (BG:insulin) ratio for blood glucose >100.
Labor and Delivery:
*Women with good glycemic control do not need delivery before 39 weeks.
- Offer cesarean with EFW >4,500g.
Monitoring:
- DM1 or DM2: Glucose testing q2-4hrs during latent phase and q1-2hrs uring active phase
- GDM: q4-6 hrs. If on diet during latent phase, then check pre- and postprandial.
- Glucose targets: >70 and <126mg/dL.
- Levels above 140-180 increase the risk of neonatal hypoglycemia and maternal ketoacidosis.
Postpartum:
- 1/3 of women with GDM with have impaired glucose tolerance or diabetes postpartum.
- 2 hr 75g GTT at 6-12 weeks postpartum for women who had GDM. (some attendings, Dr. Lawrence, prefer to obtain A1c postpartum instead).
- (fasting: 92 mg/dL; 1-hr: 180 mg/dL; and 2-hr: 153 mg/dL). If higher than thresholds, refer to PCP for management.
- The ADA recommends repeat testing at least every 3 years for women who had a pregnancy affected by GDM and normal results of postpartum screening.
- Postpartum depression is more common in women with diabetes.
Pharmacology:
- Glyburide (sulfonylurea) binds to pancreatic beta-cell adenosine triphosphate calcium channel receptors to increase insulin secretion and insulin sensitivity of peripheral tissues. (not be used in patients with sulfa allergy). Dose: 2.5-20mg in divided doses (max: 30mg).
- Metformin (biguanide): inhibits hepatic gluconeogenesis and glucose absorption and stimulates glucose uptake in peripheral tissues.
- Usually used in women on metformin for prepregnancy DM. Continue metformin dose and add insulin as needed.
- Typical Insulin starting total dosage is 0.7–1.0 units/kg daily, given in divided doses
Page updated
Google Sites
Report abuse