Recurrent Pregnancy Loss and Cardiovascular Disease Mortality in Japanese Women: A Population-Based, Prospective Cohort Study

Abstract

This study aimed to examine the association between recurrent pregnancy loss and the risk of cardiovascular disease mortality. We identified 54,652 women who were pregnant during the Japan Collaborative Cohort Study. These women were 40-79 years at the date of cohort entry between 1988 and 1990. Participants received municipal health screening examinations and completed self-administered questionnaires. The cause of death was confirmed by annual or biannual follow-up surveys for a median of 18 years. The exposure was the number of pregnancy loss. The outcome was mortality from total cardiovascular disease and its subtypes according to the International Classification of Diseases, 10th Revision. Adjustment variables included age, number of deliveries, education, body mass index, physical activity, smoking status, and drinking status. Kaplan-Meier survival curves were used to estimate the cumulative mortality. The number of pregnancy loss tended to be inversely associated with the risk of mortality from total stroke, intracerebral hemorrhage, and total cardiovascular disease. The multivariable hazard ratio of total cardiovascular disease for ≥2 pregnancy losses versus no pregnancy loss was .84 (95% confidence interval, .74-0.95). A 2-fold excess risk of mortality from ischemic stroke associated with ≥2 pregnancy losses was observed in women aged 40-59 years, with a multivariable hazard ratio of 2.19 (95% confidence interval, 1.06-4.49), but not in older women. Recurrentpregnancy loss tends to be associated with a lower risk of mortality from cardiovascular disease at 40-79 years. Younger women have an excess risk of ischemic stroke mortality associated with recurrent pregnancy loss.