Abstract
OBJECTIVE: To investigate whether women who deliver preterm have excess risk for metabolic dysregulation independent of prepregnancy factors. METHODS: We conducted a multicenter, longitudinal, observational study of 1,205 women (50% black) in the Coronary Artery Risk Development in Young Adults study with at least one birth between baseline (1985-1986) and year 25 and no metabolic syndrome or diabetes before pregnancy. Cardiometabolic factors were measured prepregnancy and at up to five subsequent examinations. We estimated the relative hazards of incident metabolic syndrome in women with one or more preterm births (less than 37 weeks of gestation, n=295) compared with only term births (37 weeks of gestation or greater, n=910). Self-reported gestational diabetes mellitus, hypertension during pregnancy, and time-dependent weight gain were also considered as covariates. RESULTS: Of 315 cases of metabolic syndrome in 17,717 person-years of follow-up, the incidence rate was higher among women with preterm compared with term births (22.0 compared with 16.4 per 1,000 person-years; relative hazard 2.91 [95% confidence interval (CI) 2.75-3.09]). After adjustment for prepregnancy cardiometabolic factors and covariates, the relative hazard (95% CI) for metabolic syndrome was 1.52 (1.22-1.88) for women with preterm compared with term births. Gestational diabetes mellitus, hypertension during pregnancy, and weight gain only modestly attenuated this association. Elevated blood pressure (36.3% compared with 26.7%, P=.002) and central adiposity (51.5% compared with 44.0%, P=.02) were the individual metabolic syndrome components that were different in women with preterm compared with term births. CONCLUSION: Women with a history of preterm birth have increased risk of incident metabolic syndrome compared with those with term births, independent of the prepregnancy metabolic status and pregnancy complications.