Influence of parity and mode of delivery on mother–infant bonding: The Japan Environment and Children's Study

Background: Although there has been an increase in reports regarding the association between perinatal risk factors and mother–infant bonding, the results have been inconsistent. Methods: This is an ongoing cohort designed study to measure the effect of environmental factors on children's health with the use of data from the Japan Environment and Children's Study. We investigated mother–infant bonding at 1 year old according to parity and mode of delivery. Results: A total of 82,540 participants, including 36,662 primipara mothers and 45,878 multipara mothers, were analyzed in the present study. Exclusive breastfeeding, marriage, and non-working factors were higher in multipara mothers than in primipara mothers. The total Mother-to-Infant Bonding Scale Japanese version (MIBS-J) score was higher (worse) in primipara than multipara (mean total: 1.129 vs. 0.897, p < 0.001). Primipara mothers also had higher anger and rejection scores than multipara mothers. When we analyzed only multipara mothers without any history of previous Cesarean section (CS), MIBS-J scores were higher in Cesarean delivery mothers than vaginal delivery mothers (p = 0.038). Limitations: We used a self-reported bonding measure. Although a self-report measure is convenient and important, an observer rating may be less susceptible to bias in perception. We did not distinguish elective CS from emergency CS, which may have different influences on mother–infant bonding. Conclusions: Primipara mothers showed worse mother–infant bonding than multipara mothers, regardless of mode of delivery. Caesarian delivery itself appears to have little effect on mother–infant bonding.