The role of oxytocin in mother-infant relations: a systematic review of human studies.

BACKGROUND Oxytocin is associated with the establishment and quality of maternal behavior in animal models. Parallel investigations in humans are now under way. This article reviews the current research examining the role of oxytocin in mother-infant relations, attachment, and bonding in humans. METHODS A systematic search was made of three electronic databases and other bibliographic sources for published research studies that examined oxytocin and mother-infant relations in humans, including attachment, maternal behavior, parenting, and mother-infant relations. RESULTS Eight studies were identified, all of which were unique in their methodologies, populations studied, and measures used. Seven studies found significant and strong associations between levels or patterns of oxytocin and aspects of mother-infant relations or attachment. CONCLUSIONS Oxytocin appears to be of crucial importance for understanding mother-infant relationships. The findings of this review suggest that the pioneering, but preliminary, research undertaken to date is promising and that replication with larger samples is needed. Research that draws on more robust measures of attachment and bonding, as well as improved measures of oxytocin that include both central and peripheral levels, will elucidate the role of oxytocin in human mother-infant relationships. As the production of oxytocin is by no means restricted to mothers, the extension of the oxytocin studies to fathering, as well as to alloparental caregiving, would be an intriguing next step.