Objective: Menopause is widely believed to be an established cause of sleep disorders, but evidence for this theory is inconclusive. Attributing any sleep problem to normal processes of menopause may lead to underdiagnosis of treatable sleep disorders in midlife women. This study uses detailed longitudinal data on sleep and menopausal health from participants in the Sleep in Midlife Women Study to investigate whether risk and severity of sleep-disordered breathing increase with progression through menopause, accounting for changes in age and body habitus. Methods: A total of 219 women aged 38 to 62 years were recruited from participants in the Wisconsin Sleep Cohort Study. Menopause status was determined from daily diaries in which participants reported menstrual flow, hot flashes, and use of hormonal medications. Each participant underwent in-home polysomnography studies every 6 months, to measure the apnea-hypopnea index (AHI) (N = 1,667 studies). Linear models with empirical standard errors were fit for logarithm of AHI on menopause status and years in menopause, adjusting for age, body mass index, waist girth, and neck girth. Results: Compared with women in premenopause, AHI was 21% higher among participants in perimenopause (95% CI, -4 to 54), 31% higher among participants in postmenopause (95% CI, 2-68), and 41% higher among participants whose menopausal stage could not be distinguished between peri-and postmenopause (95% CI, 8-82). Among women who had begun perimenopause, each additional year in menopause was associated with 4% greater AHI (95% CI, 2-6). Conclusions: Progression through menopause is associated with greater sleep-disordered breathing severity. This association is independent of aging and changes in body habitus.