Pregnant women are sensitive to the emotions and cues present in social interactions. They may exhibit heightened stress responses when support is lacking in a harmonious environment. The objective of this study was to examine the interaction of family harmony and social support and its association with stress responses among pregnant women. A total of 556 pregnant women were recruited to participate in this study. Psychological stress was measured using the Perceived Stress Scale - 10 (PSS-10). We assessed their perceived levels of family harmony (Family Harmony Scale-5: FHS-5) and social support (Multidimensional Scale of Perceived Social Support
MSPSS). They also provided blood samples for measurement of interleukin-6 (IL-6) as a marker of inflammation. Moderation analysis was conducted with estimation of regression coefficients and 95 % confidence intervals. After adjusting for covariates, the interaction of family harmony and social support in association with IL-6 levels was significant (β = -0.23, p = .045)
however, its association with psychological stress was not significant. Specifically, the lack of support within a harmonious family environment was linked to elevated levels of IL-6 in pregnant women (β = 0.26, p = .023). Social interactions lacking supportive gestures have the potential to exacerbate inflammatory responses in pregnant women. Findings underscore the importance of supportive social interactions in promoting the mental well-being of pregnant women.