Associations between neighbourhood deprivation, ethnicity and maternal health outcomes in England: a nationwide cohort study using routinely collected healthcare data

Background In the United Kingdom, pregnant women who live in the most deprived areas have two times the risk of dying than those who live in the least deprived areas. There are even greater disparities between women from different ethnic groups. The aim of this study was to investigate the role of area-based deprivation and ethnicity in the increased risk of severe maternal morbidity (SMM), in primiparous women in England.Methods A retrospective nationwide population study was conducted using English National Hospital Episode Statistics Admitted Patient Care database. All primiparous women were included if they gave birth in an National Healthcare Service (NHS) hospital in England between 1 January 2016 and 31 December 2021. Logistic regression was used to examine the relative odds of SMM by Index of Multiple Deprivation and ethnicity, adjusting for age and health behaviours, medical and psychological factors.Results The study population comprised 1 178 756 primiparous women. Neighbourhood deprivation increased the risk of SMM at the time of childbirth. In the fully adjusted model, there was a linear trend (p=0.001) between deprivation quintile and the odds of SMM. Being from a minoritised ethnic group also independently increased the risk of SMM, with black or black British African women having the highest risk, adjusted OR 1.84 (95% CI 1.70 to 2.00) compared with white women. There was no interaction between deprivation and ethnicity (p=0.49).Conclusion This study has highlighted that neighbourhood deprivation and ethnicity are important, independently associated risk factors for SMM.