Associations between Couples’ Work–Life Balance and Pregnant Women’s Quality of Life in Japan: A Cross- Sectional Dyadic Study

Background In dual-income couples, maintaining pregnant women’s quality of life (QOL) while achieving work–life balance (WLB) is essential. This study examined the association between WLB and pregnant women’s QOL among dual-income couples at different stages of pregnancy. Methods This cross-sectional, dyadic study included pregnant women and their husbands (N = 150 couples). Paired questionnaires were distributed in cooperation with obstetric facilities in Japan. Participants were categorized into the first, second, and third trimesters for stratified analysis. WLB was assessed using the Japanese version of the Survey Work–Home Interaction–Nijmegen (SWING-J), which comprises four subscales: work-to-family negative spillover (WFNS), family-to-work negative spillover, work-to-family positive spillover, and family-to-work positive spillover (FWPS). QOL was measured using the WHOQOL-BREF. Multivariate logistic regression analyses were performed after adjusting for marital relationship quality (Quality Marriage Index). Results No significant association was observed between WLB and QOL in the first and second trimesters. In the third trimester, higher WFNS among pregnant women was significantly associated with lower QOL (aOR = 0.179, 95% CI = 0.038–0.832). Regarding husbands’ WLB, higher WFNS was positively associated with pregnant women’s QOL (aOR = 11.168, 95% CI = 1.443–86.419), whereas higher FWPS was negatively associated with pregnant women’s QOL (aOR = 0.063, 95% CI = 0.007–0.554). Conclusion In the third trimester, pregnant women’s QOL was associated with both negative and positive aspects of WLB at the couple level. Higher WFNS among pregnant women and higher FWPS among husbands were associated with a lower QOL, whereas higher WFNS was associated with a higher QOL. These findings suggest that multiple WLB-related factors, both negative and positive, are linked to pregnant women’s QOL, highlighting the importance of considering complex spillover dynamics when supporting maternal well-being in dual-income households.