The objective of this study was to assess associations between maternal health-related quality of life (HRQoL) in early, mid-, and late pregnancy and birth outcomes and to assess the differences in birth outcomes between subgroups of mothers reporting relatively "low" and relatively "high" HRQoL. HRQoL was measured by the 12-item Short Form Health Survey in early (n = 6334), mid- (n = 6204), and late pregnancy (n = 6048) in a population-based mother and child cohort; Physical and Mental Component Summary (PCS/MCS) scores were calculated. Birth outcomes included pregnancy duration, preterm birth, birth weight, low birth weight, and small for gestational age. We defined very high PCS/MCS scores as the >90th percentile and very low score as the <10th percentile. The lower PCS score in late pregnancy was significantly associated with a higher chance of having small-for-gestational-age birth (per 10 points: OR = 1.20, 95% CI: 1.08, 1.33, p value = 0.0006). In early, mid-, and late pregnancy, the subgroup mothers with a low MCS score had infants with a lower average birth weight than those with very high scores (p < 0.05). The association between higher physical HRQoL in late pregnancy and a higher chance of having small-for-gestational-age birth needs further research. The role of mother's mental HRQoL during pregnancy and the potential consequences for the child require further study.
Keywords: birth outcomes; pregnancy; quality of life.