PROJECT SUMMARY/ABSTRACT Female-specific and female-predominant risk factors provide opportunities to improve cardiovascular disease (CVD) prevention and screening in women. Pregnancy complications are risk markers for future CVD revealed through the cardiometabolic “stress test” of pregnancy, which can be leveraged for early CVD prevention before the onset of established risk factors (chronic hypertension, hypercholesterolemia, type 2 diabetes). Women with a history of preeclampsia (a condition involving high blood pressure during pregnancy) or preterm delivery (<37 weeks’ gestation) have twice the risk of future CVD. Mental health conditions, such as posttraumatic stress disorder (PTSD) and depression, are twice as common in women as in men and are also associated with increased CVD risk. Although existing studies and anecdotal evidence suggest that acute adverse pregnancy outcomes (APOs; preeclampsia and preterm delivery) can constitute a traumatic event for some women and precipitate the development of mental health conditions after pregnancy, rigorous epidemiologic studies are lacking. The extent to which APOs and mental health conditions may jointly contribute to CVD in women is also unknown. This project will draw on the strengths of complementary populations and methodologic approaches, including observational epidemiologic analyses within the Nurses’ Health Study 2 and 3 (NHS2/3) prospective cohort studies and leveraging electronic health records (EHR) from the Mass General Brigham health system for both quantitative prediction modeling using machine learning and to recruit patients with recent acute APOs to participate in qualitative interviews. This research will address the gaps in the literature by: 1) evaluating the extent to which the increased CVD risk observed among women with a history of APOs is accounted for by the development of mental health conditions after pregnancy using data from NHS2/3; 2) identifying clinically relevant risk and resilience factors from the EHR that influence the risk of developing mental health conditions after an acute APO; and 3) elucidating the relationship between APOs and subsequent PTSD secondary to APO-related trauma through semi-structured qualitative patient interviews. In addition to generating new insights into the accumulation of CVD risk across a woman’s life, this proposal will provide crucial training for my development into an independent investigator by cultivating new skills in: 1) machine learning using EHR data, 2) qualitative research, and 3) psychiatric epidemiology. Given my strong background in reproductive and cardiovascular epidemiology, my world-class mentoring team, and personalized training plan to advance my skillset, I am well equipped to accomplish the proposed research. The training, mentorship, and protected time provided by this Career Development Award will uniquely position me as a leading epidemiologist equipped to improve the cardiovascular health of women.