PROJECT SUMMARY/ABSTRACT The parent R01 grant has quantified numerous obstetrical and perinatal health disparities among sex- ual minority women (SMW; e.g., those with same-sex attractions, same-sex behavior, and/or lesbian/gay/bi- sexual identity) and their offspring compared to their heterosexual counterparts using data from unique, pro- spective, intergenerational cohorts—the Nurses' Health Studies and Growing Up Today Study. Documented disparities include adverse perinatal mental health—a known contributor to adverse obstetrical and perinatal outcomes. Yet, due to small sample sizes and other methodological limitations, little is known about the mech- anisms that drive SMW's perinatal mental health inequities and how this may influence subsequent health in- equities. When forming biological and/or genetic families, many SMW in same-sex couples require specialized fertility services due to a lack of sperm within their relationship. However, negative and discriminating experi- ences, lack of provider knowledge, and barriers to accessing care are common experiences among SMW fertil- ity patients. Additionally, undergoing fertility care can be emotionally and financially distressing, and SMW are more likely to have a history of mental illness—a risk factor for perinatal mental illness. Given these considera- tions, it is prudent to understand SMW's preconception mental health and if the role of structural antecedents to the perinatal period (e.g., fertility care experiences) may uniquely influence SMW's adverse perinatal mental health. Consequently, this research will help identify whether promoting positive patient experiences and men- tal health during fertility care may serve as a critical intervention point for this population. To address these gaps, the proposed aims of this community-placed, mixed methods study are to 1) elucidate the patient experi- ence of fertility care among SMW and their partners in same-sex couples and 2) develop best practices for in- clusive family formation data collection in the Nurses' Health Studies and Growing Up Today Study. We will achieve these aims by conducting online semi-structured interviews, quantitative assessments of mental health and patient experiences, and family formation timelines—an established graphical elicitation method that pro- motes the report of temporal narratives through the co-creation of research data. This project will produce the first investigation of the patient experience of fertility care among SMW across the U.S. It will also be among the first best practices developed for accurately collecting inclusive family formation data in large population- based surveys. This work will have a positive impact on the field of SMW's perinatal health by identifying po- tential mechanisms of adverse preconception mental health and, subsequently, adverse perinatal and obstetri- cal outcomes. Additionally, this work will reconceptualize how fertility research is conducted to accurately char- ...