Association of lifetime pregnancy loss and multimorbidity with depressive symptoms among middle-aged and older Chinese women: a nationwide cross- sectional and prospective study

Background Depressive symptoms and multimorbidity are common among middle-aged and older Chinese women. Pregnancy loss is an important reproductive-life event, but whether it is independently associated with depressive symptoms decades later remains unclear. We examined the cross-sectional and prospective associations of lifetime pregnancy loss with depressive symptoms and assessed the role of multimorbidity in a nationally representative ageing cohort in China. Methods We used data from the China Health and Retirement Longitudinal Study (CHARLS), linking the 2014 life history survey with the 2015, 2018, and 2020 core waves. The cross-sectional analysis included 8,368 women aged 45 years or older in 2018. The prospective analysis included 4,145 women without depressive symptoms at baseline in 2015 who were followed through 2020. Lifetime pregnancy loss was defined as self-reported induced abortion, spontaneous abortion, or stillbirth. Depressive symptoms were defined as a 10-item Center for Epidemiologic Studies Depression Scale score of 10 or higher. Logistic regression and Cox proportional hazards models were used to estimate associations, with sequential adjustment for sociodemographic factors, health behaviors, functional status, chronic diseases, and multimorbidity. Results Among 8,368 women, 2,409 (28.8%) reported lifetime pregnancy loss. In cross-sectional analyses, pregnancy loss was associated with higher odds of depressive symptoms after adjustment for sociodemographic and behavioral factors (odds ratio [OR] 1.20, 95% confidence interval [CI] 1.08–1.34). This association attenuated after further adjustment for chronic disease and functional status (OR 1.11, 95% CI 0.99–1.24). In the prospective cohort, 2,000 incident depressive symptom events occurred over a median follow-up of 5 years. Pregnancy loss was not associated with incident depressive symptoms after full adjustment (hazard ratio [HR] 1.01, 95% CI 0.89–1.15). Women with both pregnancy loss and multimorbidity had substantially higher depressive symptom burden than women with neither exposure, both cross-sectionally (OR 2.40, 95% CI 2.07–2.78) and prospectively (HR 1.46, 95% CI 1.24–1.72). Conclusions In middle-aged and older Chinese women, lifetime pregnancy loss was associated with prevalent depressive symptoms, but this association was largely attenuated after accounting for later-life health burden and did not persist prospectively. Multimorbidity was a stronger and more consistent correlate of depressive symptoms than pregnancy loss alone. These findings suggest that reproductive history may be most informative when considered together with chronic disease burden in mental-health assessment and primary care for ageing women.