Background Maternal depression is common and associated with several child health outcomes. The impact on childhood injuries is underexplored, with existing studies relying on maternal reporting of injury occurrences. Using population healthcare databases from England, we assessed the association between maternal depression and/or anxiety episodes and rates of child poisonings, fractures, burns and serious injuries.

Methods We conducted a prospective cohort study of 207 048 mother-child pairs with linked primary care and hospitalisation data from the Clinical Practice Research Datalink and Hospital Episode Statistics, 1998–2013. Episodes of maternal depression and/or anxiety were identified using diagnoses, prescriptions and hospitalisations, with the child's follow-up time divided into exposed and unexposed periods. Adjusted IRRs (aIRR) for child injury during maternal mental health episodes were estimated using Poisson regression.

Results 54 702 children (26.4%) were exposed to maternal depression and/or anxiety when aged 0–4 years. During follow-up, 2614 poisonings, 6088 fractures and 4201 burns occurred. Child poisoning rates increased during episodes of maternal depression (aIRR 1.52, 95% CI 1.31 to 1.76), depression with anxiety (2.30, 1.93 to 2.75) and anxiety alone (1.63, 1.09 to 2.43). Similarly, rates of burns (1.53, 1.29 to 1.81) and fractures (1.24, 1.06 to 1.44) were greatest during depression with anxiety episodes. There was no association between maternal depression and/or anxiety and serious child injuries.

Conclusions Maternal depression and/or anxiety episodes were associated with increased rates of child poisonings, fractures and burns. While mechanisms are unclear, prompt identification and treatment of maternal depression and/or anxiety and provision of safety advice (eg, safe medication storage) may reduce child injury risk.