Management of Post-Term Pregnancy to Prevent Macrosomia
Risks Associated with Post-Term Pregnancy
- The American College of Obstetricians and Gynecologists recommends delivery at 38 weeks of gestation to prevent progressive macrosomia, as prolonging pregnancy beyond 38 weeks increases the risk of macrosomia without reducing the rate of cesarean sections 1, 2
- Prolonged pregnancy beyond 38 weeks specifically increases the rate of large-for-gestational-age babies without providing the benefit of reduced cesarean sections 3
Risks Specific to Gestational Diabetes
- Close monitoring is required for pregnancies at risk of stillbirth, especially when fasting glucose levels exceed 105 mg/dl or pregnancy continues beyond term 1, 2
- In undiagnosed and untreated gestational diabetes, the risk of macrosomia can reach 20% 4
- The risk of shoulder dystocia in pregnancies with diabetes and birth weight >4,500g ranges from 19.9-50%, compared to 9.2-24% in non-diabetic pregnancies 4, 5
Recommendations for Timing of Delivery
- The American Diabetes Association recommends delivery at 38 weeks of gestation to prevent progressive macrosomia, as prolonging pregnancy beyond 38 weeks increases the risk of macrosomia without reducing the rate of cesarean sections 1, 2
- There is no data to support delivery before 38 weeks in gestational diabetes without evidence of maternal or fetal complications 3
Intensive Monitoring Post-40 Weeks
- It is reasonable to intensify fetal monitoring when pregnancy continues beyond 40 weeks of gestation, although data on the risk of perinatal morbidity/mortality in well-controlled gestational diabetes is not available 3
- Mothers should be taught to monitor fetal movement during the last 8-10 weeks of pregnancy and report any reduction in perceived fetal movement immediately 3