Maternal ethnic group, socioeconomic status, and neonatal and child mortality: a nationwide cohort study in England and Wales

Background: The UK currently has one of the highest rates of child mortality in Europe. Robust population-level estimates of differences in neonatal and child mortality by ethnic and socioeconomic group are currently scarce for England and Wales. We aimed to examine variation in neonatal and child mortality by maternal ethnic group and indicators of socioeconomic status to help understand which groups are most at risk of neonatal and child mortality. Methods: In this nationwide cohort study, we used linked population-level data for England and Wales, comprising birth registrations and notifications (2011–16), Census 2011, and death registrations (2011–21). Our population was restricted to livebirths, post-24 weeks’ gestation, and to mothers aged 12 years or older at time of birth. Our primary exposures were self-reported maternal ethnic group, household socioeconomic position, and maternal education from Census 2011. We estimated mortality rates and hazard ratios from Cox proportional hazards models for different ethnic and socioeconomic groups separately for neonatal (<28 days) and child (from ≥28 days to 10 years) mortality. We adjusted for sex of baby; birth term; suspected congenital anomaly; maternal age; disability; country of birth; main language; and household tenure, region, and rural or urban location. Babies were followed from birth for up to 10 years and until Dec 31, 2021, or death, whichever occurred earlier. Findings: A total of 3 018 020 babies were included in our cohort, with the average age of the mother at delivery being 29·8 years (IQR 26–34). There were 4750 neonatal deaths and 5205 child deaths in the follow-up period. Compared with White British mothers, babies born to Pakistani mothers (hazard ratio [HR] 2·39 [95% CI 2·15–2·66]) or Black African mothers (HR 1·65 [1·43–1·91]) had the highest risk of neonatal mortality. These differences remained after fully adjusting the models for maternal, household, and gestational characteristics (adjusted HR 1·95 [95% CI 1·72–2·22] and HR 1·38 [1·15–1·66], for babies born to Pakistani and Black African mothers, respectively). The differences in child mortality by maternal ethnic group were similar and remained after accounting for maternal, household, and gestational characteristics. For socioeconomic factors, babies born to mothers with no formal education (HR 1·55 [95% CI 1·42–1·69]) or living in households with long-term unemployment (HR 1·93 [95% CI 1·69–2·19]) were most at risk from neonatal death compared with babies born to mothers who had school- level qualifications or in households where the main earner was employed in a higher managerial, administrative and professional occupation, respectively. Differences in neonatal and child mortality by education persisted for the models, accounting for maternal, household, and gestational characteristics. Interpretation: Health inequalities exist from birth; the present findings identify the most at-risk groups, which should be targeted in future research to uncover the causal pathways underpinning neonatal and child mortality. Funding: None.<p></p>