Cardiovascular disease (CVD) is the leading cause of mortality and morbidity in U.S. women at all ages, and large knowledge gaps exist in CVD predictive and preventative strategies for women. The nuMoM2b Heart Health Study (nuMoM2b-HHS) has followed a demographically diverse cohort of women enrolled and richly phenotyped during their first pregnancy, with data and biospecimens prospectively collected for up to 7 years thereafter. The overarching scientific goal of this study is to define the relationship between adverse pregnancy outcomes (APOs) and CVD to optimize CVD prediction, prevention, and treatment strategies for women. Continued follow-up of this observational cohort, building on a foundation of existing high-quality data, biospecimens, and administrative structures with a robust framework for ancillary study development and implementation, provides a unique opportunity to address knowledge gaps regarding the early mechanisms and trajectory of CVD in women.