Young children whose mothers are depressed are more prone to behavioural problems and injury, suggests US research published in Injury Prevention.
The researchers looked at the impact of maternal depression on children's behaviour and injury rates among 1106 mother and child pairs between 1992 and 1994.
The mothers and their children were all taking part in the National Longitudinal Study of Youth, which has been tracking the health of young mothers and their children from birth since 1986.
In total, 94 children, all of whom were under the age of 6, had sustained injuries, sufficient to require medical attention during the study period. Two thirds of these injuries had happened at home.
Validated scales were used to assess problem behaviour among the children and depressive symptoms among the mothers.
Children whose mothers scored persistently high marks on the depression scales were more than twice as likely to have been injured as those whose mothers had a low rating.
And children whose mothers had a high rating were significantly more likely to have behavioural problems and to "act out." Boys were more at risk of this than girls.
When analysed in more depth, the findings showed that for every 1 point increase on the depression score, the risk of injury rose by 4% and the risk of behavioural problems increased by 6%.
These findings held true after taking account of influential factors, such as household income, educational attainment and health insurance coverage.
The authors suggest that maternal depression may increase the risk of behavioural problems in the child, which may in turn boost the risk of injury.
Maternal depression might also result in less effective supervision of children or possibly an increased number of injury hazards found in the home, they add.