Presented at the Neonatal Society 2003 Summer Meeting.
Andrews DC1, Cronin A2, Morrell J2, Murray L2, Cooper P2, Johnson P1
1 Nuffield Department of Obstetrics & Gynaecology, John Radcliffe Hospital, Oxford, UK
2 Winnicott Research Unit, Dept of Psychology, University of Reading, UK.
Background: Conditions of socio-economic disadvantage and markers of stress (e.g. smoking, anxiety, depression) are believed to impact on fetal and infant biophysiological development. Furthermore, such adversity often relates to Sudden Infant Death Syndrome (SIDS). The objective of this study was to investigated the interaction between psychosocial status and biophysiological development. The effects on maternal and infant sleep wake organisation including settling to sleep strategies are reported.
Methods: Low (LR, 64) and high (HR, 58) risk primiparous mothers were recruited into the study grouped by an index of social adversity, risk for depression and lifestyle factors associated with SIDS. Sleep/wake patterns, measures by the light/dark ration (LD ratio) from activity monitoring were measured in mother infant pairs at 10days, 4, 7, & 12 weeks postnatally. Settling to sleep strategies were measured y questionnaire. The sleeping environment was assessed by video analysis in a sub sample at 12w (n=60). Repeated maternal and infant outcome measurements were analysed using multilevel models.
Results: HR infants had a lower LD ratio than LR infants at 12w (p=0.005), while HR mothers had lower LD ratio at 4, 7 and 12 weeks (p=0.02, p=0.007 and p<0.001 respectively). Both risk groups had similar numbers of awakenings in the night at 12w, but once awake, HR infants were awake for longer (p=0.03, n=60). HR mothers were less likely to use infant settling strategies that encouraged infant autonomy (p=0.005), and more likely to engage in social interaction (p<0.001) with accompanying high levels of environmental activity (p<0.01).
Conclusions: Antenatal high risk for maternal psycho-social adversity and SIDS identified significant differences in infant care practices and development of infant sleep wake organisation postnatally. Sleep/wake patterns differed substantially between HR and LR mothers as did their parenting practices, with HR mothers using more active strategies in a livelier environment whilst settling their infants to sleep. The infants of LR mothers developed a more marked diurnal pattern than HR infants by 12 weeks which is likely to related to a more unsettled night in HR infants.