Impact of socioeconomic conditions and perinatal factors on risk of becoming a child looked after: a whole population cohort study using routinely collected data in Wales

Background: Between 1997 and 2021, the number of Children Looked After (CLA) in Wales, UK,increased steadily, with stark inequalities. We aimed to assess how deprivation and maternal and child perinatal characteristics influence risk of becoming CLA in Wales. Study design: We constructed a prospective longitudinal cohort of children born in Wales between April 2006 and March 2021 (n=395,610) using linked administrative records. Methods: Survival models examined the risk of CLA from birth by small-area deprivation, maternal and child perinatal characteristics. Population attributable fractions quantify the potential impact of action on modifiable risk factors. Results: Children from the most deprived fifth of the population were 3.4 times more likely to enter care than those in the least deprived (demographic adjusted hazard ratios HR 3.40, 95% CI 3.08, 3.74). Maternal mental health problems in pregnancy (fully adjusted hazard ratios, aHR, 2.03, 95% CI 1.88, 2.19) and behavioural factors, child congenital anomalies (aHR 1.46, 95% CI 1.16-1.84), low birth weight (aHR 1.28, 95% CI 1.17, 1.39) and pre-term birth (aHR 1.16, 95% CI 1.06, 1.26) were associated with higher risk of CLA status. Risk of CLA in the population may be reduced by 35% (95% CI 0.33, 0.38) if children in the two most deprived fifths of the population experienced the conditions of those in the least deprived. Conclusions: Deprivation and perinatal maternal health are important modifiable risk factors for children becoming CLA. Our analysis provides insight into the mechanisms of intergenerational transfer of disadvantage in a vulnerable section of the child population, and identifies targets for public health action