An Update on Screening Strategies for Gestational Diabetes Mellitus: A Narrative Review

Abstract

Gestational diabetes mellitus (GDM) is a frequent medical complication during pregnancy. Screening and diagnostic practices for GDM are inconsistent across the world. This narrative review includes data from 87 observational studies and randomized controlled trials (RCTs), and aims to give an overview of the current evidence on screening strategies and diagnostic criteria for GDM. Screening in early pregnancy remains controversial and studies show conflicting results on the benefit of screening and treatment of GDM in early pregnancy. Implementing the one-step "International Association of Diabetes and Pregnancy Study Groups" (IADPSG) screening strategy at 24-28 weeks often leads to a substantial increase in the prevalence of GDM, without conclusive evidence regarding the benefits on pregnancy outcomes compared to a two-step screening strategy with a glucose challenge test (GCT). In addition, RCTs are needed to investigate the impact of treatment of GDM diagnosed with IADPSG criteria on long-term maternal and childhood outcomes. Selective screening using a risk-factor-based approach could be helpful in simplifying the screening algorithm but carries the risk of missing significant proportions of GDM cases. A two-step screening method with a 50g GCT and subsequently a 75g oral glucose tolerance test (OGTT) with IADPSG could be an alternative to reduce the need for an OGTT. However, to have an acceptable sensitivity to screen for GDM with the IADPSG criteria, the threshold of the GCT should be lowered from 7.8 to 7.2 mmol/L. A pragmatic approach to screen for GDM can be implemented during the COVID-19 pandemic, using fasting plasma glucose (FPG), HbA1c or even random plasma glucose (RPG) to reduce the number of OGTTs needed. However, usual guidelines and care should be resumed as soon as the COVID pandemic is controlled.

First-Trimester Triglyceride-Glucose Index and Risk of Pregnancy-Related Complications: A Prospective Birth Cohort Study in Southeast China

“…Reportedly, the total incidence of PRCs can reach approximately 5% to 30% in mainland China. [4][5][6] PCRs (eg, preeclampsia and GDM) not only affect direct adverse pregnancy outcomes such as placental disease, preterm delivery, fetal distress, and intrauterine growth retardation, 7,8 but also contribute to maternal postpartum cardiovascular and metabolic morbidity. 9 Thus, more data are needed to identify the clinical risk factors of PRCs as early as possible.…”

Disparities in Incidences of Cesarean Section Among Women With Gestational Diabetes Mellitus in the United States

“…In the United States, 2-10% of all pregnancies develop GDM annually. Screening for GDM usually occurs after 24 weeks in asymptomatic women or those without risk factors for diabetes mellitus [ 3 ]. However, women with risk factors for GDM should undergo screening during the first antenatal care visit.…”

Screening of Gestational Diabetes and Its Risk Factors: Pregnancy Outcome of Women with Gestational Diabetes Risk Factors According to Glycose Tolerance Test Results

“…Currently there is no generally accepted screening group or “gold standard” test to define the disease status. In most centers, the oral glucose tolerance test (OGTT) is applied but the testing strategy and diagnostic criteria vary [ 7 , 8 ]. In 2010, the International Association of Diabetes and Pregnancy Study Groups (IADPSG) recommended the use of 75 g OGTT at 24–28 gestational weeks with a cut-off point of fasting venous plasma glucose ≥5.1 mmol/L and/or after 1 h and 2 h level of ≥10.0 mmol/L and ≥8.5 mmol/L, respectively [ 9 ].…”