From the Guidelines
For women with well-controlled gestational diabetes who reach 39 weeks without spontaneous labor, induction of labor is generally recommended. This approach is supported by the findings of the ARRIVE trial, which demonstrated that elective induction of labor at 39 weeks in low-risk nulliparous women did not result in statistically significant differences in primary perinatal outcomes compared to expectant management, but did show reductions in the rate of primary cesarean delivery and hypertensive disorders of pregnancy 1. Although the ARRIVE trial did not specifically focus on women with gestational diabetes, its results can be applied to this population as a means of minimizing the risks associated with continuing the pregnancy, such as fetal overgrowth, shoulder dystocia, and stillbirth.
Key considerations for induction of labor in this context include:
- Cervical readiness, which may influence the choice of induction method
- Close monitoring of blood glucose levels, aiming for targets between 70-120 mg/dL during labor
- The potential need for intravenous insulin infusion to maintain target glucose levels
- The possibility of macrosomia and associated complications, which are increased in gestational diabetes despite good blood glucose control
Given the potential benefits and the lack of evidence suggesting harm, induction of labor at 39 weeks is a reasonable approach for women with well-controlled gestational diabetes who have not gone into spontaneous labor. This recommendation aligns with the principle of balancing the risks of continuing the pregnancy against those of early delivery, with the goal of optimizing outcomes for both mother and fetus 1.
From the Research
Recommendations for Labor at 39 Weeks in Well-Controlled Gestational Diabetes
- There are no specific recommendations provided in the given studies for labor at 39 weeks in well-controlled gestational diabetes.
- However, the studies suggest that gestational diabetes mellitus (GDM) increases the risk of fetal macrosomia, which can lead to complications during delivery, such as shoulder dystocia, clavicle fractures, and brachial plexus injury 2.
- The risk of macrosomia is higher in GDM pregnancies, even if blood glucose levels are controlled within normal ranges 3.
- Hyperglycemia in GDM pregnancies can promote trophoblast cell proliferation via ERK1/2 signaling, which may contribute to the development of macrosomia 4.
- Placental glucose transport and utilization are affected in insulin-treated GDM pregnancies, with reduced glucose utilization in pregnancies without macrosomia 5.
- The American College of Obstetricians and Gynecologists (ACOG) recommends that women with well-controlled GDM be induced at 39 weeks of gestation to reduce the risk of complications, but this is not explicitly stated in the provided studies.
Key Considerations
- Fetal macrosomia is a common adverse infant outcome of GDM, and its risk increases with poor glucose control 2.
- Placental abnormalities, including increased placental size and villous immaturity, are common in GDM pregnancies 6.
- The molecular mechanism of hyperglycemia on trophoblast cells in vitro involves the activation of ERK1/2 signaling, which promotes cell proliferation 4.