Stress and depression risk in pregnancy associates with altered immune function

Objectives: Psychological factors such as well-being, stress, and depression can influence immune function, with dysregulated inflammation during pregnancy contributing to adverse outcomes. While the role of inflammatory markers has been studied in pregnancy complications like preterm birth and preeclampsia, few studies explore how psychological states impact cellular and serum immune responses in pregnant women. In this study, we investigated associations between psychological factors and inflammatory markers from peripheral blood mononuclear cells (PBMCs) and serum in early and late pregnancy. Methods: This secondary analysis of 70 pregnant women from the MicrobeMom2 RCT investigated associations between psychological factors and inflammatory markers from peripheral blood mononuclear cells (PBMCs) and serum in early and late pregnancy. Wellbeing, stress, and depression risk were assessed using the WHO-5 Well-being Index, Perceived Stress Questionnaire, and Edinburgh Postnatal Depression Scale. Associations between immune markers and psychological factors were analysed using independent t-tests, ANOVA, and linear regression. Results: Higher well-being correlated with lower leptin levels in late pregnancy serum. Higher stress scores were associated with decreased PBMC-secreted TNF-α in early pregnancy. Increased depression risk was associated with lower serum TNF-α and ICAM1 in early pregnancy and reduced IL17A in late pregnancy. Conclusions: Well-being, stress, and depression risk are associated with an altered immune response during early and late pregnancy, which may contribute to the relationship between suboptimal psychological states and adverse pregnancy outcomes.