Pregnancy Loss Was Associated With the Increased Risk of Cardiovascular Diseases in Middle-Aged Women: Evidence From the China Health and Retirement Longitudinal Study

Objectives: Significant associations between pregnancy loss and risk of future maternal cardiovascular disease (CVD) have been found in Western countries, but the association in China is still unclear. Therefore, this study aimed to investigate the associations of pregnancy loss, number of pregnancy losses, subtype of pregnancy loss (i.e. induced abortion, miscarriage and stillbirth) and age at the first pregnancy loss with CVD risk in Chinese population. Methods: We examined data of 7,486 middle-aged women (mean age 58.1 years) from the China Health and Retirement Longitudinal Study. Pregnancy loss and CVD including coronary heart disease (CHD) and stroke were self-reported and documented in surveys. Results: In the cohort, 1,850 (24.7%) women experienced pregnancy loss. Over 39 years follow-up, 2,055 (27.5%) women developed CVD. After adjusting covariates, pregnancy loss was associated with the risk of CVD (HR 1.73, 95% CI 1.56 to 1.92). Specifically, pregnancy loss due to induced abortion and miscarriage instead of stillbirth increased CVD (HR 2.11, 95% CI 1.82 to 2.44, and 1.47, 95% CI 1.16 to 1.72, respectively). The risk of CVD gradually increased from ≤23 years to 23-25, 26-29 and ≥30 years with HR 1.29, 95% CI 1.24 to 1.34. Conclusion: Chinese women that have experienced pregnancy loss due to induced abortion and miscarriage had increased risk of CVD. The risk increased with the number of pregnancy losses and older age at the first pregnancy loss.