Factor Structure of the Parental Bonding Instrument for Pregnant Japanese Women

The parental bonding instrument (PBI) is often used to examine the perceptions of children and adolescents regarding parenting practices. Previous studies have investigated the factor structure of the PBI. However, although it is important to examine the relationships between the perceived parenting practices and perinatal mental health, few studies have included perinatal women. We aimed to accurately clarify which PBI factor structure was useful in assessing perinatal women (n = 4633). Furthermore, we evaluated the measurement invariance between primipara and multipara groups, and between the paternal and maternal PBI forms. Our exploratory and confirmatory factor analyses revealed that a three-factor PBI structure was most plausible for perinatal women. Moreover, we found complete invariance (residual invariance) of the PBI ratings across primipara and multipara women for the paternal and maternal forms. In contrast, we found weak invariance (metric invariance) of the PBI ratings across the paternal and maternal forms. Our participants tended to rate fathers as less caring and less overprotective than mothers. This three-factor structure shows measurement invariance in perinatal women and can be used to accurately determine how the perceived parenting style before adolescence influences women's mental health in the perinatal period.