Factors associated with new onset of father-to-infant bonding failure from 1 to 6 months postpartum: an adjunct study of the Japan environment and children's study.

Purpose: This study aimed to determine the factors associated with new onset father-to-infant (paternal) bonding failure from 1 to 6 months postpartum.

Methods: This was a prospective birth-cohort study. Paternal bonding failure was evaluated using the Japanese version of the Mother-to-Infant Bonding Scale (MIBS-J) at 1 and 6 months postpartum. For cut-off scores, overall bonding failure, MIBS-J total scores ≥ 5; subscale for lack of affection, MIBS-J_LA scores ≥ 3; and subscale for anger/rejection, MIBS-J_AR scores ≥ 3 were used in this study. Multivariate regression analysis was performed to analyze relative variables.

Results: We analyzed 872 fathers. The frequency of new-onset overall bonding failure, lack of affection, and anger/rejection was 5.6%, 4.9%, and 6.3%, respectively. For new-onset overall bonding failure, significant associated factors were paternal childcare leave (adjusted odds ratio [AOR] 3.192; 95% confidence interval [CI] 1.203-8.469), paternal new-onset depression symptoms (AOR 3.181; 95% Cl 1.311-7.716), and maternal new-onset overall bonding failure (AOR 4.595; 95% Cl 1.119-18.866). For new-onset lack of affection, significant associated factors were preterm birth (AOR 4.189; 95% Cl 1.473-11.913) and paternal new-onset depression symptoms (AOR 3.290; 95% Cl 1.294-8.362). For new-onset anger and rejection, significant associated factors were paternal childcare leave (AOR 3.142; 95% Cl 1.138-8.676), paternal new-onset depression symptoms (AOR 2.829; 95% Cl 1.133-7.068), and maternal new-onset anger/rejection (AOR 7.064; 95% Cl 2.300-21.700).

Conclusions: The factors associated with new-onset paternal bonding failure from 1 to 6 months postpartum were paternal childcare leave, preterm birth, paternal postpartum depression symptoms, and maternal bonding failure.