What is the recommended delivery approach for a 29-year-old woman, 37 weeks pregnant, with a history of gestational diabetes mellitus (GDM) and a body mass index (BMI) of 26.6 kg/m², presenting with a transverse lie?

Management of Transverse Lie at 37 Weeks in a Patient with Gestational Diabetes

A transverse lie at 37 weeks gestation requires external cephalic version (ECV) attempt, and if unsuccessful or contraindicated, delivery should be by planned cesarean section at 39 0/7 to 39 6/7 weeks of gestation given her diet-controlled GDM with good glycemic control.

Immediate Management of Transverse Lie

Transverse lie is an absolute indication for cesarean delivery if it persists at term. The primary management decision is whether to attempt external cephalic version before proceeding to cesarean section.

External Cephalic Version Considerations

• ECV should be offered as the first-line approach for malpresentation at term, though success rates vary and the procedure carries risks including placental abruption, cord compression, and emergency cesarean delivery
• The presence of GDM is not a contraindication to ECV attempt, provided glycemic control is adequate 1
• If ECV is successful and cephalic presentation is achieved, vaginal delivery may be pursued following standard obstetric protocols

Cesarean Delivery Planning

If ECV fails, is declined, or is contraindicated, planned cesarean section is mandatory for transverse lie.

Timing of Delivery with Diet-Controlled GDM

For women with diet-controlled GDM and good glycemic control without maternal vascular complications, delivery should occur during the 39th week of gestation (39 0/7 to 39 6/7 weeks). 2

Key Timing Principles

• Do not deliver before 38 completed weeks in uncomplicated diet-controlled GDM, as this increases neonatal morbidity 1, 2
• Delivery at 38 weeks is recommended to prevent progressive macrosomia, as prolongation beyond 38 weeks increases macrosomia risk without reducing cesarean rates 1, 3
• However, the optimal window is 39 0/7 to 39 6/7 weeks for diet-controlled GDM with good control 2, 4
• GDM alone is not an indication for delivery before 38 weeks 1, 3

Pre-Delivery Assessment Requirements

Fetal Growth Assessment

• Ultrasound assessment for estimated fetal weight (EFW) is mandatory before delivery planning 2
• Scheduled cesarean delivery should be considered if EFW exceeds 4,500 grams due to significantly increased risks of shoulder dystocia (19.9-50% vs 9.2-24% in non-diabetic pregnancies) and brachial plexus injury 3, 4
• If EFW is >4,000 grams, discuss risks and benefits of prelabor cesarean delivery 4

Glycemic Control Verification

• Confirm adequate glycemic control with targets of fasting <95 mg/dL and either 1-hour postprandial <140 mg/dL or 2-hour postprandial <120 mg/dL 1
• If fasting glucose levels exceed 105 mg/dL, increased surveillance for fetal compromise is warranted 1, 3

Maternal Surveillance

• Monitor blood pressure and urine protein at each visit to detect preeclampsia, as GDM increases risk of hypertensive disorders 1
• Teach fetal movement monitoring during the last 8-10 weeks and instruct immediate reporting of reduced movements 1, 3

Critical Pitfalls to Avoid

• Never perform cesarean delivery solely because of GDM diagnosis - the transverse lie is the indication for cesarean, not the GDM 1, 2
• Do not deliver before 38 weeks based on GDM alone without evidence of maternal or fetal compromise 1, 2, 3
• Do not allow pregnancy to continue beyond 40 weeks without intensified fetal surveillance, as data on perinatal outcomes in well-controlled GDM beyond this point are limited 1, 3

Specific Considerations for This Patient

BMI and Weight Management

• With a BMI of 26.6 kg/m² (overweight category), this patient should receive counseling on appropriate gestational weight gain 1
• Modest energy restriction (30% reduction) may be appropriate if needed for glycemic control, but avoid ketonemia 1

Postpartum Planning

• Reclassification of glucose tolerance is mandatory at 4-12 weeks postpartum using a 75g OGTT with non-pregnancy criteria 1
• Lifestyle modifications are essential postpartum, as women with GDM have greatly increased risk of type 2 diabetes 1
• Breastfeeding should be encouraged as it may reduce subsequent diabetes risk 1