Association of parity with the prevalence of hypertension in Japan: The Tohoku Medical Megabank Community-based cohort study.

This study investigated the association of parity with hypertension prevalence in Japanese women while considering a clinical history of hypertensive disorders of pregnancy (HDP) and menopausal status. This cross-sectional study included 30,530 Japanese women (6700 premenopausal; 23 830 postmenopausal). The association between parity and the prevalence of hypertension was evaluated using a multiple logistic regression model with possible confounders. In premenopausal women, no statistically significant association between parity and hypertension prevalence was found. When not adjusted for current body mass index (BMI), a linear graded association was observed between parity and the prevalence of hypertension in postmenopausal women. However, the association between parity and hypertension prevalence in postmenopausal women was attenuated after adjustment for current BMI. Both current BMI and a clinical history of HDP were significantly associated with a high risk of hypertension in both premenopausal and postmenopausal women. Our results also suggest that continuous surveillance and preventive measures for hypertension should be provided for women with HDP and high parity.