Research is currently limited on the impact of maternal and especially paternal postpartum bonding on child social-emotional development. This study is part of the nationally representative CHILD-SLEEP -sample (n = 710 families), where postpartum bonding was assessed with Postpartum Bonding Questionnaire (PBQ) at the child age of eight months, and child social-emotional problems were assessed with the Five to Fifteen (FTF) and the Strengths and Difficulties Questionnaire (SDQ) at child age of five years. Both maternal and paternal postpartum bonding difficulties at eight months were associated with child externalizing, internalizing and peer problems at five years. When parental depressive symptoms were controlled, the association remained significant only with internalizing problems. When investigating joint maternal and paternal bonding, we found both cumulative and mother-driven effects with child internalizing problems. The results emphasize the role of early parental bonding for later child mental health, highlighting the importance of early parental support.

The authors have declared no competing interest.

This work was supported by the Academy of Finland (grant numbers 134880, 308588, 342747, 351492), the Gyllenberg Foundation, the Yrjo Jahnson Foundation, the Foundation for Pediatric Research, the Finnish Cultural Foundation.

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The details of the IRB/oversight body that provided approval or exemption for the research described are given below:

Ethics committee of Pirkanmaa Hospital District gave ethical approval for this work (9.3.2011, ethical research permission code R11032).

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