Ethnic differences in the association between gestational diabetes and pregnancy outcome

The purpose of the study was to examine ethnic variation in the impact of Gestational Diabetes Mellitus (GDM) on birth outcome. The authors examined the association between GDM and pregnancy-induced hypertension, macrosomia, primary Cesarean delivery, and preterm birth, using New York City Birth Certificate data from 2001-2006. Logistic regression was used to evaluate the crude and adjusted odds ratios of GDM with each adverse perinatal event, stratified by ethnicity. GDM was associated with increased risk of adverse perinatal events among all ethnic groups, with modest variation by ethnicity. Across ethnic groups, adjusted odds ratios comparing women with and without GDM ranged from 1.4-2.9 for pregnancy-induced hypertension, 1.0-2.2 for macrosomia, 1.1-1.8 for primary Cesarean delivery, and 1.3-1.8 for preterm birth. Overall, Caribbean, Sub-Saharan African, and African American women tended to show a larger relative impact of GDM, while North African, South Central Asian, and Chinese women showed a comparatively smaller impact of GDM. Although some ethnic variation was seen, differences in effect size were not large enough to support ethnic-specific thresholds for GDM diagnosis and treatment.