Racial/ethnic differences in the percentage of gestational diabetes mellitus cases attributable to overweight and obesity, Florida, 2004-2007.

Introduction: Gestational diabetes mellitus (GDM) affects 3% to 7% of pregnant women in the United States, and Asian, black, American Indian, and Hispanic women are at increased risk. Florida, the fourth most populous US state, has a high level of racial/ethnic diversity, providing the opportunity to examine variations in the contribution of maternal body mass index (BMI) status to GDM risk. The objective of this study was to estimate the race/ethnicity-specific percentage of GDM attributable to overweight and obesity in Florida.

Methods: We analyzed linked birth certificate and maternal hospital discharge data for live, singleton deliveries in Florida from 2004 through 2007. We used logistic regression to assess the independent contributions of women's prepregnancy BMI status to their GDM risk, by race/ethnicity, while controlling for maternal age and parity. We then calculated the adjusted population-attributable fraction of GDM cases attributable to overweight and obesity.

Results: The estimated GDM prevalence was 4.7% overall and ranged from 4.0% among non-Hispanic black women to 9.9% among Asian/Pacific Islander women. The probability of GDM increased with increasing BMI for all racial/ethnic groups. The fraction of GDM cases attributable to overweight and obesity was 41.1% overall, 15.1% among Asians/Pacific Islanders, 39.1% among Hispanics, 41.2% among non-Hispanic whites, 50.4% among non-Hispanic blacks, and 52.8% among American Indians.

Conclusion: Although non-Hispanic black and American Indian women may benefit the most from prepregnancy reduction in obesity, interventions other than obesity prevention may be needed for women from other racial/ethnic groups.