Association between pregnancy loss and depressive symptoms in women: a population-based study.

Background: Depression is a common mental disorder with a much higher prevalence in women than in men. Although there has been a gradual increase in research on the association between reproductive health and depression, there is still some inconsistency in the evidence of the relationship between pregnancy loss and depression. This study aimed to investigate the relationship between pregnancy loss and depressive symptoms.

Methods: We analyzed data from the 2007-2020 National Health and Nutrition Examination Survey (NHANES), which included female participants aged 20 to 80 years. Pregnancy loss was determined based on participants' self-reported number of pregnancies and pregnancy outcomes. Depressive symptoms were measured using the Patient Health Questionnaire (PHQ-9, score ≥ 10). Multivariate logistic regression, smoothed curve fitting, and generalized additive modeling were used to examine the association between pregnancy loss and depression. We also performed sensitivity analyses and subgroup analyses to verify the robustness and specificity of the findings.

Results: A total of 12,873 female participants were included in our study, of which 1,595 (12.39%) were categorized as depressed. Multivariate logistic regression results indicated that experiencing a pregnancy loss increased the risk of prevalence of depression in women (for 1 loss: OR = 1.31, 95% CI 1.15,1.50; for 2 or more losses: OR = 1.58, 95% CI 1.38, 1.81). When sensitivity analyses were performed, an association between pregnancy loss and depression was found in both multivariate linear regressions with PHQ-9 scores as a continuous variable and multivariate logistic regressions with a threshold of 5 PHQ-9 scores. The association between pregnancy loss and depression remained stable across subgroups.

Conclusion: Pregnancy loss correlated with elevated PHQ-9 scores and a heightened risk of depression in adult women across the United States. Focusing on the incidence of adverse pregnancy events in the female population may help prevent or early recognize the onset of depression.