The U.S. Preventive Services Task Force (USPSTF) recommends gestational diabetes mellitus (GDM) screening at or after 24 weeks of pregnancy in asymptomatic individuals. This recommendation forms the basis of a draft recommendation statement published online Feb. 16.

Jennifer Pillay, from the University of Alberta Evidence-Based Practice Center in Edmonton, Canada, and colleagues conducted a systematic literature review to update the USPSTF recommendations on the benefits and harms of GDM screening. Data were included from 18 trials and 87 . The researchers found that four observational studies of screening versus no screening indicated an association for screening with a for some pregnancy and neonatal outcomes. Being diagnosed but not treated for GDM was associated with increased risks, including preeclampsia, cesarean delivery, and macrosomia. Based on nine trials, treatment of mild GDM at or after 24 weeks of gestation was associated with a reduced risk for primary cesarean deliveries, preterm deliveries, preeclampsia, macrosomia, large for gestational age, birth injuries, and neonatal intensive care unit admissions.

Based on these findings, the USPSTF concludes there is moderate net benefit to GDM screening at 24 weeks of gestation to improve maternal and fetal outcomes (B recommendation). The evidence for screening for GDM in asymptomatic individuals before 24 weeks of gestation is currently insufficient to assess the balance of benefits and harms (I statement).

The draft statement and evidence review have been posted for public comment; comments can be submitted Feb. 16 to March 15, 2021.