Screening Tests for Gestational Diabetes: A Systematic Review for the U.S. Preventive Services Task Force

Abstract

The OGCT and fasting plasma glucose level (at a threshold of 4.7 mmol/L [85 mg/dL]) by 24 weeks' gestation are good at identifying women who do not have GDM. The OGCT is better at identifying women who have GDM. The OGCT has not been validated for the IADPSG diagnostic criteria.

Screening For Gestational Diabetes Mellitus

“…However, O'Connor et al [53] investigated the normal values for HgbA1c in pregnancy in non-diabetic women and identified a normal reference interval of 4.3-5.4% in the first trimester [53]. Because of the high rates of false-positive and false-negative findings, serum HbA1c values cannot be recommended for screening GDM [40] USPSTF also supports this conclusion [38].…”

“…HgbA1c has limited efficacy in the diagnosis of GDM during the third trimester, demonstrating moderate sensitivity (85.7%) and poor specificity (61.1%) [40,49]. The American Diabetes Association (ADA) and the International Association of Diabetes in Pregnancy Study Group (IADPSG) support its use during pregnancy.…”

“…The American Association of Clinical Endocrinologists (AACE) and the ADA in 2011 recommend screening of all women without a pregestational diabetes at 24-28 weeks' gestation with a 75-g 2-h oGTT [40].…”

“…The Preventive Services Task Force (USPSTF), the United Kingdom National Health Service and the Canadian Task Force didn't report any sufficient high-level evidence about costeffectiveness of routine GDM screening [38]. In the United States of America (USA), most obstetricians prefer universal screening with an initial 50-g glucose challenge test (GCT) [39][40][41]. Very recently, the Canadian Diabetes Association (CDA) not only recommends the same sequential universal screening approach, but also offers an alternative with one-step 75-g oral glucose tolerance test (OGTT) [42].…”

“…Before 28 weeks fetal growth acceleration has already began,so screening after 28 weeks isn't logical. For healty women without anamnestic risk factors GDM screening and diagnosis is performed between 24 and 28 weeks [7,[38][39][40].…”