C76-09 Association Between Obstructive Sleep Apnea and Hypertensive Disorders of Pregnancy

Abstract Background Obstructive sleep apnea (OSA) is a sleep-related breathing disorder characterized by intermittent upper airway obstruction and episodes of hypoxia. Although OSA affects around 3%-7% of reproductive-age women, its prevalence in pregnancy is likely underestimated due to limited screening. Prior studies report OSA in up to 15-20% of obese pregnant women and nearly 50% in those with BMI ≥40 kg/m². Hypertensive disorders are known risk factors for OSA, yet their association with pregnancy-specific outcomes remains underexplored. This study examined OSA prevalence among pregnant women in the Sutter Health System and its association with HDP. Methods We conducted a retrospective analysis using electronic health records from the Sutter Health System. The cohort included pregnant women aged 18-45 who delivered between January 2022 and December 2024. OSA and HDP were identified using ICD-9 and ICD-10 codes from inpatient, outpatient, and obstetric encounters. Pregnancy episodes were defined using the earliest and latest pregnancy-related diagnostic codes. BMI, age, and race/ethnicity were extracted. Descriptive and chi-square analyses assessed associations between OSA and HDP. Results Among 73,265 deliveries, 1.4% (n = 1,028) had an OSA diagnosis. Of these, 515 were diagnosed before or during pregnancy and 513 postpartum. The mean BMI among women with OSA was 30.1. Among those diagnosed prior to or during pregnancy, the largest racial groups were non-Hispanic White (29.3%) and Hispanic (27.8%). When adjusted for total deliveries, OSA prevalence per 1,000 deliveries was highest among Black (9.3) and Hispanic (8.4) women, followed by White (6.3) and Asian (6.2). Twenty-one percent of women with OSA had HDP compared to 7% without OSA, including 7.8% with preeclampsia, 12.8% with preexisting hypertension, and 1.0% with primary hypertension. Conclusion OSA was identified in 1.4% of pregnant patients, with higher prevalence among Black and Hispanic women, highlighting existing disparities. Women with OSA had a threefold higher rate of HDP compared to those without OSA. These findings highlight the need for improved screening, early diagnosis, and targeted management of OSA during pregnancy to reduce adverse maternal outcomes. This abstract is funded by: None