The Impact of Parental Personality on Birth Outcomes: A Prospective Cohort Study

OBJECTIVE: To investigate the effect of parental personality on birth outcomes. DESIGN: Prospective cohort study. SETTING: 727 pregnant women and 579 spouses receiving antenatal care at a single-center in rural Tokyo, Japan during 2010–2013. METHODS: We measured the association between maternal effect of parental personality traits assessed by the Cloninger’s Temperament and Character Inventory on birth outcomes, using multiple regression and adjusting for demographics. RESULTS: Maternal self-transcendence personality was inversely associated with gestational age [-0.26 (95% confidence interval (CI): -0.51 to -0.01) weeks per unit] and positively associated with preterm birth [odds ratio (OR) 2.60 (95% CI: 1.00 to 6.75) per unit], while paternal self-transcendence personality was positively associated with gestational age [0.31 (95% CI: 0.07 to 0.55) weeks per unit]. Maternal reward dependence was positively associated with fetal growth [0.30 (95% CI: 0.02 to 0.59) per unit]. Other maternal and paternal personality traits associated with adverse maternal behavior, such as novelty seeking, harm avoidance and self-directedness, were not associated with birth outcomes. CONCLUSION: We found that specific parental personality traits can be associated with birth outcomes.