Background Women who deliver preterm infants (<37 weeks) have excess cardiovascular risk; however, it is unclear whether the unfavorable changes in the cardiometabolic profile associated with preterm delivery initiate before, during, or after childbearing. Methods and Results We identified 1306 women (51% Black) with births between baseline (1985-1986) and year 30 in the CARDIA (Coronary Artery Risk Development in Young Adults) study. We compared life course changes in blood pressure, body mass index, waist circumference, and lipids in women with preterm deliveries (n=318) with those with all term deliveries (n=988), using piecewise linear mixed-effects models. Specifically, we evaluated group differences in rates of change before and after the childbearing period and change in level across the childbearing period. After adjusting for the covariates, women with preterm deliveries had a higher change in diastolic blood pressure across the childbearing period than those with all term deliveries (1.59 versus -0.73 mm Hg, P<0.01); the rates of change did not differ by group, both prechildbearing and postchildbearing. Women with preterm deliveries had a larger body mass index increase across the childbearing period (1.66 versus 1.22 kg/m2, P=0.03) compared with those with all term deliveries, followed by a steeper increase after the childbearing period (0.22 versus 0.17 kg/m2 per year, P=0.02). Conclusions Preterm delivery was associated with unfavorable patterns of change in diastolic blood pressure and adiposity that originate during the childbearing years and persist or exacerbate later in life. These adverse changes may contribute to the elevated cardiovascular risk among women with preterm delivery.