Is socioeconomic inequality in postnatal depression an early-life root of disadvantage for children?

This paper investigates the role that socioeconomic inequality in postnatal depression might play in intergenerational transmission of inequality. Infants' development is thought to be particularly sensitive to mothers' mental health at this time, suggesting that greater early-life exposure to maternal depression among disadvantaged groups might be a root of later socioeconomic inequalities. Heightened contact with health services during this period presents opportunities for intervention, but higher unmet need for treatment of postnatal depression among the disadvantaged might be widening inequalities. The aim of this study is to quantify the potential contribution of postnatal depression to socioeconomic inequalities in adverse childhood health and development outcomes. Regression-based decomposition of the concentration index is used to explore the association between income inequality in postnatal depressive symptoms and income inequality in children's outcomes. Four problems of early adolescence are explored: emotional and conduct problems, special educational needs, and low self-assessed health. Data are taken from the UK Millennium Cohort Study, with a sample of 4359 mothers and children with complete data on outcomes and covariates, and a second sample of 5441 when missing covariates are filled using multiple imputation. The key finding is that socioeconomic inequality in maternal postnatal depression is a significant contributor to inequalities in special educational needs, emotional problems, and low self-assessed health for children at age 11 years, even after accounting for a range of other factors that might explain such associations. These findings highlight the importance of understanding the impact of postnatal depression interventions on inequalities, and the downstream influence on children's outcomes. Addressing inequalities in mothers' postnatal depression might be an avenue for reducing early-life disadvantage for children.