Repeat Late GDM Testing and Cesarean Delivery Rates

Impact of Late Gestational Diabetes Detection and Treatment on Cesarean Delivery Rates After Negative Initial Screening

The goal of this randomized trial is determine if re-testing for gestational diabetes in the third trimester after an ultrasound measurement of estimated fetal weight (EFW) or abdominal circumference greater than 90%ile decreases cesarean delivery rate, and to evaluate the optimal method of re-testing. The main question it aims to answer is:

Does repeat testing for gestational diabetes and management of hyperglycemia decrease the cesarean delivery rate in fetuses measuring >90%ile by estimated fetal weight (EFW) or abdominal circumference (AC) on ultrasound in the third trimester.

Participants will be randomized into two groups: Group 1 will undergo a repeat glucose tolerance test (GTT) with blinded continuous glucose monitor (CGM) and group 2 will have no intervention. Participants in group 1 will receive nutrition counseling as this would be standard in patients at high risk for gestational diabetes.

This will be a prospective randomized control trial to determine if re-testing for gestational diabetes in the third trimester after an ultrasound measurement of estimated fetal weight (EFW) or abdominal circumference greater than 90%ile decreases cesarean delivery rate, and to evaluate the optimal method of re-testing. Pregnant women will be recruited with gestational age between 30 weeks and 36 weeks gestation with an ultrasound that demonstrates a fetus with either estimated fetal weight (EFW) >90%, abdominal circumference (AC)>90% or both. They will be randomized into two groups: Group 1 will undergo a repeat glucose tolerance test (GTT) with blinded continuous glucose monitor (CGM) and group 2 will have no intervention. Participants in group 1 will receive nutrition counseling as this would be standard in patients at high risk for gestational diabetes.

The primary outcome is cesarean delivery. Labor course, complications, and delivery/neonatal data will be obtained.

Inclusion Criteria:

• Gestational age 30 weeks 0 days and 36 weeks 6 days
• Ultrasound with estimated fetal weight or abdominal circumference greater than 90th%ile
• Age 18-50 years old.

Exclusion Criteria:

• Previously diagnosed gestational diabetes or pre-gestational diabetes
• Multiple gestation
• Previous cesarean delivery
• Any condition precluding vaginal delivery (placenta previa/placenta accreta spectrum disorders, vasa previa, prior uterine surgery with contraindication to vaginal delivery)
• Suboptimal dating (based on US >22wk gestation)
• Contraindication to glucose tolerance test