Background Language is one of the most important acquisitions made during childhood. Before verbal language, a child develops a range of skills and behaviours that allow the child to acquire all communication skills. Factors such as environmental factors, socio-economic status and interaction with parents can affect the acquisition of vocabulary in children. Post-partum depression can negatively affect the first interactions with the child and, consequently, the emotional, social and cognitive development of the child.
Objective To analyse the effect of the duration of the mother's depression on the language development of children at 12 months old.
Methods This was a longitudinal study. The participants of this study were mothers who had received prenatal care from the Brazilian National System of Public Health in Pelotas city, State of Rio Grande do Sul, Brazil. The mothers were interviewed at two different time points: from 30 to 90 days after delivery and at 12 months after delivery; the children were also evaluated at this later time point. To diagnose maternal depression, we used the Mini International Neuropsychiatric Interview, and to assess child development, we used the language scale of the Bayley Scales of Infant Development III.
Results We followed 296 dyads. Maternal depression at both time points (post partum and at 12 months) was significantly associated with the language development of infants at 12 months of age. This impact was accentuated when related to the duration of the disorder. Older women and women with more than two children were more likely to have children with poorer language development, while women who were the primary caregiver had children with higher scores on the language test.
Conclusion The findings indicate that maternal age, parity, primary caregiver status and duration of post-partum depression are associated with the language development of the child.