Comparison of Two Screening Strategies for Gestational Diabetes (GDM2) (GDM2)

This is a single site blinded RCT of 920 pregnant women with singleton gestation designed to compare the Carpenter-Coustan and IADPSG criteria for diagnosing gestational diabetes. Maternal metabolic profiles and infant growth will be assessed at randomization and at one year postpartum.

Study Overview

• Status: Completed
• Conditions: Glucose Intolerance; Pregnancy; Gestational Diabetes
• Intervention / Treatment: Diagnostic test: Gestational diabetes screening with fasting 3 hour 100 gm; Diagnostic test: Gestational diabetes screening with fasting 2 hour 75g

Detailed Description

Impaired glucose metabolism (gestational diabetes (GDM) and mild hyperglycemia) that occurs during pregnancy is associated with an increased risk for pregnancy complications and is also an early indication of long-term metabolic dysfunction leading to diabetes and cardiovascular disease. In the US, GDM is diagnosed using a two-step screening and diagnostic approach. The International Association of Diabetes and Pregnancy Study Group (IADPSG) proposed a one-step diagnostic approach that broadens the definition of GDM by lowering the cutoff values to include women with milder forms of hyperglycemia, who would have screened normal under the current two-step approach. The goal of these recommendations is better identification of women at risk for pregnancy complications and long-term metabolic dysfunction, but it results in a significant increase in the prevalence of GDM. The NIH GDM Consensus Development Conference committee does not recommend changing from the current two-step screening/diagnostic approach to the IADPSG one-step diagnostic approach without trials demonstrating that increasing the number of women diagnosed as having GDM results in better outcomes. We aim to 1) conduct a "real world" randomized controlled trial (RCT) to determine differences in short-term perinatal health outcomes between the two predominant GDM screening approaches, and 2) prospectively follow the mothers to examine their metabolic risk profiles and the growth of their infants at 1 year postpartum. Based on a pilot study, we propose a single site blinded RCT of 920 pregnant women ages 18-45 years without a diagnosis of diabetes, with a singleton pregnancy (18-24 wks gestation). Participants will have a non-fasting 1 hour 50 gm glucose challenge test (GCT) performed between 24-28 weeks' gestation. Women with 50 gm GCT results < 200 mg/dL will be randomized to receive either a fasting 2 hour 75 gm oral glucose tolerance test (OGTT) or a 3 hour 100 gm OGTT. GDM will be diagnosed using the IADPSG criteria for women receiving the 75 gm OGTT and Carpenter-Coustan criteria for women receiving the 100 gm. Participants and their physicians will be informed of the diagnosis of GDM, but blinded to the specific test results and diagnostic criteria. Participants with GDM will receive treatment from their primary provider. Questionnaires will be used to assess participants' and physicians' views on GDM testing. Metabolic profiles will be assessed at randomization and at a year postpartum. The primary outcome measure is large-for-gestational age fetal growth. The rationale for this RCT is that this is a unique opportunity to compare the two methods. At the end of the study, we will know whether women diagnosed at lower glucose levels with the IADPSG criteria are more likely to have adverse perinatal outcomes. We hypothesize that using IADPSG diagnostic criteria will result in greater detection of women with impaired glucose metabolism and treating these women will reduce adverse perinatal outcomes and prevent long-term metabolic dysfunction. This study will provide level A data for endorsing universal screening guidelines for GDM by major organizations and implementation into clinical care.

• Study Type: Interventional
• Enrollment (Actual): 921
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • Pennsylvania
    • Pittsburgh, Pennsylvania, United States, 15213
      • UPMC- Magee Womens Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 45 years (Adult)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: Female

Description

Inclusion Criteria:

• Pregnancy between 18-24 weeks of gestation
• Singleton gestation
• Planning to deliver at Magee-Womens Hospital, Pittsburgh, Pennsylvania

Exclusion Criteria:

• Preexisting type 1 or 2 diabetes
• Diabetes diagnosed at less than 24 weeks gestational age (GA)
• Multiple gestations ( e.g. twins or triplets)
• Hypertension requiring medications
• Corticosteroid (IM, oral or IV) use in the 30 days prior to enrollment
• Major congenital anomaly with anticipated preterm delivery due to maternal or fetal indications < 28 wks GA
• Inability to complete the glucose testing before 30 completed weeks GA
• Advanced HIV( on medications that cause hyperglycemia), severe liver disease, gastric bypass surgery or other illness/surgeries that preclude them from drinking the glucola solution.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Screening
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Quadruple

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: 3 hour 100 gm OGTT (CC Criteria); Gestational diabetes screening with fasting 3 hour 100 gm. Receive a fasting 3 hour 100 gram oral glucose tolerance test and are diagnosed based on the Carpenter Coustan Criteria: a 50 gm Glucose tolerance test of >130 + fasting 3 hour 100 gram oral glucose tolerance test with two or more values greater than the following diagnostic threshold: Fasting 95, 1-hour 180, 2-hour 155, or 3 hour 140 mg/dL . A positive criteria will be diagnostic for gestational diabetes.	Diagnostic test: Gestational diabetes screening with fasting 3 hour 100 gm; Participants receive fasting 3 hour 100 gm oral glucose tolerance test
Active Comparator: 2 hr 75 gm OGTT (IADPSG Criteria); Gestational diabetes screening with fasting 2 hour 75g. Receive a fasting 2 hour 75 gm oral glucose tolerance test and diagnosed based on the IADPSG which is if one or more values exceed the following diagnostic threshold: Fasting 92, 1-hour 180, or 2-hour 153 mg/dL.	Diagnostic test: Gestational diabetes screening with fasting 2 hour 75g; Participants receive fasting 2 hour 75 gm oral glucose tolerance test

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Large for Gestational Age (LGA) Infant	birth weight equal to or greater than the 90th percentile for gestational age and sex	at time of delivery

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Cesarean Delivery	the delivery of a baby through a surgical incision in the mother's abdomen and uterus	at delivery (approximately 40 weeks' gestation)
Maternal Composite Morbidity	maternal pre-eclampsia, 3rd or 4th degree vaginal lacerations, post-partum hemorrhage	at delivery (approximately 40 weeks' gestation)
Neonatal Composite Morbidity	1) hypoglycemia: blood glucose < 40mg/dl); 2) hyperbilirubinemia requiring treatment, clinical jaundice; 3)hyperinsulinemia- measured with c peptide level from venous cord blood; 4) still birth- absence of fetal heart tones before delivery, 5) birth trauma= Shoulder dystocia/brachial plexus injuries.	7 days after birth

Collaborators and Investigators

• Sponsor: Esa M Davis, MD MPH FAAFP
• Collaborators: Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD)
• Investigators: Principal Investigator: Esa M Davis, MD MPH, University of Pittsburgh

Publications and helpful links

General Publications

• Abebe KZ, Scifres C, Simhan HN, Day N, Catalano P, Bodnar LM, Costacou T, Matthew D, Illes A, Orris S, Duell J, Ly K, Davis EM. Comparison of Two Screening Strategies for Gestational Diabetes (GDM2) Trial: Design and rationale. Contemp Clin Trials. 2017 Nov;62:43-49. doi: 10.1016/j.cct.2017.08.012. Epub 2017 Aug 18.
• Davis EM, Abebe KZ, Simhan HN, Catalano P, Costacou T, Comer D, Orris S, Ly K, Decker A, Mendez D, Day N, Scifres CM. Perinatal Outcomes of Two Screening Strategies for Gestational Diabetes Mellitus: A Randomized Controlled Trial. Obstet Gynecol. 2021 Jul 1;138(1):6-15. doi: 10.1097/AOG.0000000000004431.

Study record dates

Study Major Dates

• Study Start (Actual): August 11, 2015
• Primary Completion (Actual): July 3, 2019
• Study Completion (Actual): June 5, 2020

Study Registration Dates

• First Submitted: November 25, 2014
• First Submitted That Met QC Criteria: December 2, 2014
• First Posted (Estimate): December 5, 2014

Study Record Updates

• Last Update Posted (Actual): July 20, 2020
• Last Update Submitted That Met QC Criteria: July 2, 2020
• Last Verified: July 1, 2020

More Information

Terms related to this study

• Keywords: gestational diabetes screening; Carpenter Coustan Criteria; IADPSG criteria; Large for gestational age birth weight
• Additional Relevant MeSH Terms: Glucose Metabolism Disorders; Metabolic Diseases; Endocrine System Diseases; Pregnancy Complications; Hyperglycemia; Diabetes Mellitus; Glucose Intolerance; Diabetes, Gestational
• Other Study ID Numbers: PRO14070556; R01HD079647 (U.S. NIH Grant/Contract)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: Once the study is completed and the investigators have published the main manuscripts regarding the outcomes of the trial. De-identified data will be made available by request, review and approval of the investigators and the institution regulatory committee.
• IPD Sharing Time Frame: Data will be shared in the appropriate time frame required by policy.
• IPD Sharing Access Criteria: An application and review process will be implemented for accessing data.
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL; SAP

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: Yes