Stroke during pregnancy and the postpartum period: A nationwide population-based study in South Korea

Pregnancy-associated stroke (PAS) is a rare but clinically important complication of pregnancy. Despite its clinical significance, nationwide data on PAS are lacking in South Korea, a representative country with advanced maternal age.

This study aimed to investigate the incidence, temporal trends, and risk factors of PAS in South Korea.

We retrospectively analyzed nationwide data from the Korean National Health Insurance Service (NHIS) to identify women of reproductive age (15-49 years) who delivered between 2014 and 2021. PAS was defined as an ischemic or hemorrhagic stroke occurring during pregnancy or within 6 weeks postpartum. Multivariable logistic regression analysis was performed to identify independent predictors of PAS.

Of 2,000,110 deliveries between 2014 and 2021, 909 first-ever strokes occurred during pregnancy or within 6 weeks postpartum, including 500 ischemic (55%) and 409 hemorrhagic (45%) strokes. The overall incidence of PAS was 45.6 per 100,000 deliveries (95% confidence interval (CI), 42.7-48.6) and increased from 41.5 in 2014 to 51.0 in 2021 (p = 0.049), mainly driven by ischemic stroke. PAS occurred predominantly during the postpartum period (p < 0.0001) and among older women (p for trend < 0.0001). In multivariable analysis, advanced maternal age (odds ratio [OR] per year, 1.02; 95% CI, 1.01-1.05), hypertension (OR, 2.04; 95% CI, 1.37-3.04), migraine (OR, 1.33; 95% CI, 1.02-1.74), gestational hypertension (OR, 1.49; 95% CI, 1.04-2.12), pre-eclampsia/eclampsia (OR, 5.00; 95% CI, 3.59-6.96), and peripartum cardiomyopathy (OR, 14.26; 95% CI, 4.48-45.42) were identified as independent predictors of PAS.

The incidence of PAS is increasing in South Korea, with advanced maternal age, vascular risk factors, and pregnancy-related complications serving as independent predictors. These findings emphasize the importance of clinical awareness and the identification of women at high risk of PAS.