This predicted risk calculator is based on the following article:

Donovan BM, Breheny PJ, Robinson JG, Baer RJ, Oltman SP, Saftlas AF, Bao W, Greiner AL, Carter KD, Rand L, Jelliffe-Pawlowski LL, and KK Ryckman (2019). Development and validation of a clinical model for preconception and early pregnancy risk prediction of gestational diabetes mellitus in nulliparous women. PLoS One, 14(4): e0215173.

Additional details concerning the model:

• Pre-pregnancy body mass index is calculated from height and weight prior to pregnancy or during the first prenatal visit
• These estimates were calculated within a population of singleton women who delivered at greater than 30 weeks gestation and did not have pre-existing type 1 or type 2 diabetes mellitus. Estimated risk predictions may not be accurate when applied to women not meeting these criteria.
• Women with a predicted risk greater than 6% are considered to be high risk for developing GDM and may benefit from lifestyle (dietary and/or physical activity) interventions.

Accuracy of the model: Among all nulliparous women, the area under the curve (AUC) was 0.732 (95% confidence interval (CI) 0.728-0.735) for the California internal validation cohort and 0.710 (95% CI 0.672, 0.749) for the Iowa external validation cohort. When stratified by race/ethnicity, the model showed the strongest performance among Hispanic (California internal validation cohort: AUC 0.739) and Black (California internal validation cohort: AUC 0.719) women. The model had moderate predictive performance among White, not Hispanic women (California internal validation cohort: AUC 0.693, Iowa external validation cohort: AUC 0.723), Hawaiian/Pacific Islander women (California internal validation cohort: AUC 0.715), and women in other racial groups (California internal validation cohort: AUC 0.713). The weakest predictive performance was observed among Asian women (California internal validation cohort: AUC 0.665). The model could not be tested within the American Indian/Alaska Native group in the California internal validation cohort and any racial/ethnic group other than White, not Hispanic in the Iowa external validation cohort due to the small number of subjects with the outcome of interest.

For questions about the design and analysis of the study, contact Kelli Ryckman. For questions about the web application, contact Patrick Breheny.