Assessing the impact of social determinants of health on rising preterm birth trends in England. A longitudinal ecological study, 2012–17

BACKGROUND: Preterm birth (PTB) is the UK's leading cause of neonatal morbidity and mortality. There is international evidence of socioeconomic inequalities in PTB. Between 2012 and 2017, the proportion of live births occurring prematurely increased in England. This study explores how changes to major social determinants of health (SDH) may have contributed to recent trends. METHODS: We analysed PTB trends and their correlation with contemporaneous trends in major SDH predictors (socioeconomic status, income, and unemployment) for English Local Authorities. We used both fixed-effects and mixed-effects modelling to estimate the association between SDH and PTB rates between 2012 and 2017. RESULTS: The gap in PTB inequalities widened over the study period, with the absolute difference in PTB rates between most and least disadvantaged communities rising by 35%. Mixed-effects analysis demonstrated an association between the proportion of children living in low-income households and PTB; for each percentage point increase in child poverty, an estimated additional 0.24 per 1000 births was preterm. CONCLUSION: We provide evidence of rising PTB rates in England prior to the pandemic, which disproportionately affected the poorest areas of the country. Policies targeting areas with higher child poverty rates are likely to reduce inequalities in PTB in England.