Background Post-natal depression is common and has been associated with adverse effects on children's later emotional and behavioural development. The evidence for effects on children's cognitive development is unclear but this could potentially be a major public health issue. The aim was to examine whether maternal depression and maternal caregiving during the first year of life are associated with children's subsequent language development.
Methods One thousand two hundred and one women were recruited from antenatal and post-natal baby clinics in two areas in England, and followed up until their babies were 3 years. Mothers and children were assessed by questionnaire, interview and home observation; 999 children's language was assessed at 36 months, although 55 were excluded principally because they had been exposed to insufficient English.
Results In bivariate analyses maternal depressive symptomatology in the post-natal year but not at 36 months was associated with poorer child language at 36 months; maternal caregiving, was positively associated with language. Structural Equation Modelling revealed that depression was associated with poorer caregiving but was not independently associated with language. Higher quality caregiving at 10 months was associated with better language. When the sample was split by socioeconomic factors the effects of depression on caregiving were stronger in the less advantaged group. In both groups poorer quality early caregiving predicted lower language outcome.
Conclusions Post-natal depression had a negative effect on caregiving, which in turn affected language; post-natal depression did not have an additional direct effect on language. Socioeconomic factors moderated the effects of depression on caregiving. When targeting interventions at mothers with post-natal depression, it may be strategic to focus on lower socioeconomic groups at higher risk.