Does raising the glucose challenge test threshold impact birthweight in Asian gravidas?*
Some authors suggest a glucose challenge test (GCT) threshold of 150 mg/dL in Asian gravidas. The impact of such a policy on outcomes is unknown.Study Design
A retrospective cohort of 1705 Asian gravidas. Subjects (n = 95) had a GCT of 140–150 mg/dL and underwent a 3-h glucose tolerance test (GTT). Matched controls (n = 190) had a GCT of <140 mg/dL. Birthweight was the primary outcome and the secondary outcomes were cesarean delivery (CD) rate and macrosomia.Results
Eight subjects (11.9%) had gestational diabetes mellitus (GDM); none had GTT fasting values of >90 mg/dL. Mean birthweight was 3282 g in the subjects and 3238 g in the controls (P = 0.39). There were no significant differences in the secondary outcomes.Conclusion
Compared with controls, study patients did not deliver significantly larger infants. However, raising the GCT threshold would have missed 8 subjects (11.9%) with GDM. Raising the GCT threshold to 150 mg/dL in Asian gravidas may unacceptably lower the sensitivity of the screening test.