Self-Administered 2-Hour Oral Glucose Tolerance Test

Gestational diabetes affects up to 10% of pregnancies, with increasing prevalence. Due to the risk of developing overt type 2 diabetes mellitus, patients are recommended to complete postpartum diabetes screening within 4-12 weeks of delivery. Despite these recommendations, screening rates remain low. Research evaluating reasons for low screening have identified social barriers like lack of transportation or childcare, as well as health literacy barriers. The consequences of missed screening include delay in diagnosis, delay in care, and ultimately higher health burden for the patient and the healthcare system.

This study seeks to evaluate a novel approach to increase uptake of recommended postpartum diabetes screening. The primary objective of this study is to determine if a self-administered postpartum diabetes screen (75-gram oral glucose tolerance test) increases screening completion rates. Our hypothesis is that the ability to perform the 75-gram oral glucose tolerance test at home will improve compliance with screening.

Additionally, we will evaluate the level of patient satisfaction with virtual follow-up in the intervention arm as a pre-specified additional outcome.

Eligible, consenting participants will be enrolled and randomized in a 1:1 ratio to the control arm (routine postpartum care with office-based diabetes screen) or intervention arm (self-administered diabetes screen). The randomization sequence will be generated by the study statistician using a block design. Investigators will remain masked to the randomization sequence.

All participants will be asked to complete a brief survey containing patient characteristics and two questions about perceived risk. Additional patient and neonatal data will be abstracted from the electronic medical record. All information will be stored in a secure password protected database.

Participants allocated to the intervention arm will receive the 75-gram oral glucose load and instructions prior to hospital discharge. The test should be administered approximately 4 weeks after delivery, and this date will be provided. They will be scheduled for a virtual visit approximately 4 weeks after delivery to report their results and discuss appropriate follow-up. Following this visit, participants will be asked to complete a modified version of the Telehealth Usability Questionnaire. The questionnaire contains five questions about their satisfaction with their telemedicine experience. The scoring is based on a likert scale, 1-7, with higher scores indicating higher satisfaction. If patients do not attend their 4-week virtual visit, they will be contacted one additional time to complete.

Participants will be scheduled for a routine 6-week postpartum visit.

Control arm participants will attend their routine 6-week postpartum visit where the postpartum diabetes glucose screen will be ordered. They can complete the test that day if they are fasting or will be responsible for arranging test completion on another day.

The study will conclude 12 weeks after delivery for each participant. At that time, any patients who have not completed the recommended postpartum diabetes screening will be contacted to ensure they have not completed screening outside of our health system/electronic medical record. If they are successfully contacted, they will be reported in intent-to-treat fashion based on self-reported completion of recommended screening.

Inclusion criteria

• Maternal age 18 years or older
• English or Spanish speaking
• Diagnosis of gestational diabetes with recommendation for postpartum screening, by any of the following criteria (1) HgbA1c 5.9-6.4% at ≤ 14 6/7 weeks, (2) HgbA1c ≥ 5.9% at 15-23 6/7 weeks, (3) 50-gram oral glucose tolerance test plasma glucose value ≥ 200 mg/dL, (4) 2 or more abnormal plasma glucose values on a 100-gram oral glucose tolerance test with the following thresholds: fasting ≥ 95 mg/dL, 1 hour ≥ 180 mg/dL, 2 hour ≥155 mg/dL, 3 hour ≥140 mg/dL or (5) fasting blood glucose ≥ 126
• No personal history of Type 1 or Type 2 diabetes defined by self-reported or documented history, or HgbA1c >/=6.5% at ≤ 14 6/7 weeks gestation
• Antepartum care with Prisma Health affiliated obstetric practices
• Delivery at Greenville Memorial Hospital
• Active Epic MyChart access at time of enrollment
• Capable of providing informed consent

Exclusion criteria

• Pre-pregnancy diagnosis of diabetes (Type 1, 2, or other form of diabetes)
• No glucometer or supplies for fingerstick glucose monitoring, or inability to perform fingerstick glucose monitoring
• Unable to provide informed consent
• Inability to follow up for routine postpartum care