How pre-pregnancy body mass index influences health-related quality of life during pregnancy: a serial multiple mediation analysis.

BACKGROUND: Recent studies have suggested pre-pregnancy body weight plays a role in women's health-related quality of life (HRQOL) during pregnancy. However, the mechanisms underlying this relationship remain unclear. This study aims to explore the associations between pre-pregnancy body mass index (BMI) and HRQOL during pregnancy, focusing on the potential mediating roles of depressive symptoms, sleep disturbances, and general health perception. METHODS: A cross-sectional correlational study was conducted with 240 pregnant Korean women using self-report questionnaires. A multi-mediation path model was developed to assess the interrelationships among variables. Path analysis was performed using AMOS 26.0, and serial multiple mediation analysis with phantom variables was used to evaluate the mediating roles of sleep disturbances, depressive symptoms, and health perception. RESULTS: The proposed path model demonstrated a good fit, explaining 56.8% of the variance in pregnant women's HRQOL. Pre-pregnancy BMI showed relationships with HRQOL indirectly through sleep disturbances, depressive symptoms, and general health perception, indicating no direct association between pre-pregnancy BMI and HRQOL during pregnancy. Among the hypothesized paths, however, the path of sleep disturbance → HRQOL and the sequential path of pre-pregnancy BMI → sleep disturbance → HRQOL were not significant. These findings suggest that although sleep disturbance does influence HRQOL, its effect is largely mediated through depressive symptoms and general health perception. CONCLUSIONS: To promote HRQOL during pregnancy, healthcare professionals should educate women of reproductive age on the importance of maintaining a healthy BMI before conception. Additionally, prenatal care should incorporate simultaneous screening for sleep disturbances and depressive symptoms, particularly among women with elevated pre-pregnancy BMI.