Summary Sleep disordered breathing is associated with hypertensive disorders of pregnancy as well as severe maternal morbidity, both major causes of maternal mortality. SDB is also associated with obesity and diabetes, considered as major contributors to severe maternal morbidity and maternal mortality. These outcomes have also been associated with poor long term maternal cardiovascular and metabolic health, have a tremendous public health impact both perinatally and long term, and are the source of a major cost burden. Treatment of sleep disordered breathing with positive airway pressure in pregnancy has been shown to improve blood pressure after one night of therapy and in randomized controlled trials; however, long term treatment has been complicated by low adherence. This study proposes to perform in depth interviews with young women participants with sleep apnea, pregnant and non-pregnant, to understand the barriers and facilitators to PAP adherence in this population, and focus on pregnancy specific barriers. We also propose to examine differences in barriers and facilitators by race in pregnant women. Women (pregnant and non-pregnant) diagnosed with sleep apnea and initiated on PAP therapy by a clinician will be enrolled to participate in in-depth interviews examining barriers and facilitators common to all PAP users -but that could be impacted by pregnancy physiology-, as well as pregnancy specific barriers. We will perform purposive sampling to enroll PAP- adherent and PAP-nonadherent women, as well as non-adopters of PAP therapy to better understand their various perspectives. We will then examine responses in Black and non-Black women to identify differences by race that may relate to communication, messaging, or cultural differences. PAP adherence will be assessed by downloading data from PAP devices, and interpreting such data in the context of sleep and activity data by using a headband to measure sleep and an actigraphy wrist monitor to measure activity and sleep cycles. This study will enable the development of effective, culturally sensitive counseling strategies to ensure optimal adherence to PAP, an intervention that improves hemodynamic measures in women with preeclampsia as well as glucose metabolism in women with gestational diabetes. In the general population PAP therapy has been shown to hasten clinical recovery in stroke, and improve cardiac function and functional outcomes in patients with heart failure, conditions that are major causes of severe maternal morbidity and mortality.