PROJECT SUMMARY/ABSTRACT Poor sleep quality is highly prevalent during pregnancy, and is associated with increased risk of numerous adverse maternal psychological and health outcomes. Despite this, there is limited research on interventions to improve sleep during pregnancy. Further, prior research has not targeted the unique factors contributing to poor sleep quality in this population, such as discomfort and pain. Mindfulness-based interventions, such as mindfulness-based childbirth and parenting (MBCP), are particularly well-suited to improve psychological responses to discomfort and pain, and pregnant women prefer non-pharmacological interventions due to concerns about side effects. However, there is a paucity of research optimizing and evaluating mindfulness- based interventions to improve prenatal sleep quality. To this end, the proposed project will optimize MBCP to improve prenatal sleep quality (MBCP-PS) and conduct pilot testing. The candidate will use state-of-the-art experience sampling methods to identify the psychological responses to nightly physical symptoms that are most robustly associated with poor sleep quality during pregnancy. Based on these findings and feedback from focus groups, the candidate will select MBCP components to maximally impact the identified targets. Finally, the candidate will conduct a pilot randomized controlled trial of MBCP-PS versus treatment as usual to investigate safety, acceptability, adherence, and feasibility, and examine preliminary evidence of change in psychological responses to nightly physical symptoms, and associations with sleep quality. Findings will provide preliminary data for an R61/R33 application to further optimize MBCP-PS and conduct an adequately powered randomized controlled trial. The proposed Mentored Patient-Oriented Research Career Development Award (Parent K23) provides substantive hands-on experiences and training in: 1) delivery and research of mindfulness-based and other mind-body interventions, 2) mechanism-focused intervention development and analysis, 3) women's perinatal health, and 4) sleep physiology, assessment, and intervention. The candidate will carry out the proposed work within an outstanding research environment. She has assembled an exceptional team of renowned mentors and specialized advisors with deep expertise on these topics to closely guide her proposed projects, and who are dedicated to her career development. The proposed award will provide the candidate with the in-depth experiences needed to establish an independent program of research focused on optimizing and evaluating mindfulness-based interventions for promoting women's health during the perinatal period.