Does oxytocin modulate variation in maternal caregiving in healthy new mothers?
BACKGROUND
Maternal sensitivity to infant cues and developmental needs may be pivotal for social and cognitive development. Animal and recent human studies emphasise a major role for Oxytocin (OT) in mediating sensitive caregiving but no study has examined the relationship between OT and extreme variation in human maternal sensitivity.


METHODS
From 105 expectant mothers, 80 underwent blind-rating of maternal sensitivity at 4-6 months postpartum through free-play interaction with their infants. At 7-9 months postpartum, 30 mothers at extremes of maternal sensitivity: 15 'sensitive mothers' (high sensitivity mothers - HSMs, mean=4.47; SD=0.74) and 15 'less sensitive mothers' (low sensitivity mothers - LSMs, mean=2.13; SD=0.52) underwent plasma OT measurements before and after 10 min infant play.


RESULTS
Baseline and post-interaction plasma OT was higher in LSMs than HSMs [F(1, 26)=8.42; p=0.01]. HSMs showed a trend towards significant reduction in plasma OT [t(14)=2.01; p=0.06] following play-interaction; no change was shown by LSMs [t(13)=-0.14; p=0.89]. Conclusion Higher baseline OT levels in healthy LSMs may imply greater stress responses to the demands of caring for an infant, or past deficiencies in own parenting relationship and act as a biomarker for poor parental sensitivity. OT may be acting to reduce stress and anxiety in LSMs consistent with studies of plasma OT and stress in women. By contrast, in HSMs, play interaction with their infants maybe relaxing as indicated by significant reduction in plasma OT from baseline. Ascertainment of mothers in well-defined sensitivity groups might facilitate examination of distinct coping strategies in parents and better understanding of variation in parental caregiving behaviour and its potential for modulation by OT. This article is part of a Special Issue entitled Oxytocin and Social Behav.
Institute of Brain, Behaviour and Mental Health, University of Manchester, Manchester M13 9PL, UK. Electronic address: kathryn.m.abel@manchester.ac.uk.
Alya
A
Elmadih
Institute of Brain, Behaviour and Mental Health, University of Manchester, Manchester M13 9PL, UK.
Ming Wai
MW
Wan
Michael Numan, Rio Rancho, NM 87144, United States. Electronic address: numan@bc.edu.
Michael
M
Numan
Neuroscience and Psychiatry Unit, Institute of Brain, Behaviour and Mental Health, University of Manchester, Manchester M13 9PL, UK.
Rebecca
R
Elliott
Neuroscience and Psychiatry Unit, Institute of Brain, Behaviour and Mental Health, University of Manchester, Manchester M13 9PL, UK.
Darragh
D
Downey
Institute of Brain, Behaviour and Mental Health, University of Manchester, Manchester M13 9PL, UK.
Kathryn M
KM
Abel
D000328:Adult; D005260:Female; D006801:Humans; D007223:Infant; D007398:Interpersonal Relations; D008297:Male; D008425:Maternal Behavior / Q000502:physiology*; D009034:Mother-Child Relations / Q000523:psychology; D009035:Mothers / Q000523:psychology*; D010121:Oxytocin / Q000097:blood*; D016487:Parenting / Q000523:psychology*; D010988:Play and Playthings; D013315:Stress, Psychological
D010121:Oxytocin
Maternal sensitivity; Mother–infant interaction; Natural variation; Plasma oxytocin; Stress