Women who experience adverse pregnancy outcomes may face a higher risk of atrial fibrillation (AF) decades later, according to findings published in JAMA Cardiology.

This national cohort study included 2,201,047 women in Sweden who had singleton deliveries between 1973 and 2015. Over 54 million person-years of follow-up, 51,173 women (2.3%) were diagnosed with AF at a median age of 63 years.

All adverse pregnancy outcomes except small-for-gestational-age births were associated with an increased risk of AF. Within 10 years after delivery, the highest adjusted hazard ratios (HRs) were observed for hypertensive disorders (HR 1.69; 95% CI, 1.32–2.15), preterm delivery (HR 1.46; 95% CI, 1.26–1.70), and large-for-gestational-age births (HR 1.16; 95% CI, 1.01–1.32). At 30 to 46 years after delivery, risk remained elevated in women with hypertensive disorders (HR 1.44; 95% CI, 1.24–1.66), preeclampsia (HR 1.38; 95% CI, 1.33–1.50), gestational diabetes (HR 1.19; 95% CI, 1.03–1.37), large-for-gestational-age births (HR 1.17; 95% CI, 1.14–1.21), and preterm delivery (HR 1.11; 95% CI, 1.07–1.16).

These associations were largely unexplained by shared familial factors, indicating an independent contribution of pregnancy complications to AF risk. The findings highlight the need for early preventive strategies and long-term cardiovascular monitoring among women with adverse pregnancy outcomes.