Antenatal outcomes for women with multiple long-term conditions in pregnancy: a UK-wide retrospective cohort study.

Abstract

Around 20% of pregnant women in the UK have multiple long-term conditions (MLTCs), defined as two or more physical or mental health conditions. The current evidence related to adverse maternal outcomes at a population level is scarce. The aim of this study was to compare antenatal outcomes between women with and without MLTCs across the four UK nations. This retrospective cohort study included pregnant women aged 15-49 years from England, Northern Ireland, Scotland, and Wales. Data sources included Clinical Practice Research Datalink Gold (CPRD; 2000-22), Born in Bradford (2006-10), Secure Anonymised Information Linkage (2000-19), Scottish routine health records (2010-19), and the Northern Ireland Maternity System (2011-21). MLTCs were defined using a list of 79 health conditions developed with input from women and clinicians, with the number of conditions recorded including the mental health conditions. Antenatal outcomes included miscarriage, venous thromboembolism, gestational hypertension, pre-eclampsia, gestational diabetes, obstetric cholestasis, vomiting and hyperemesis, and antenatal mental health outcomes (anxiety and depression). Modified Poisson regression was used to estimate the association between MLTCs and antenatal outcomes separately for each dataset, adjusting for maternal age, gravidity, ethnicity, deprivation, BMI, smoking, and year of pregnancy. Pooled estimates across datasets were derived through meta-analysis when outcomes were available. Miscarriage and termination of pregnancy were reported using CPRD only, whereas antenatal anxiety and depression were pooled across datasets when ascertainment was available. A total of 2 225 701 pregnancies or birth events were analysed. Compared with women without MLTCs, those with MLTCs had increased risks of antenatal complications, including hyperemesis (adjusted risk ratio 1·69 [95% CI 1·58-1·81]), vomiting (1·61 [1·46-1·78]), miscarriage (1·20 [1·18-1·22]), gestational diabetes (1·26 [1·18-1·34]), gestational hypertension (1·18 [1·13-1·22]), obstetric cholestasis (1·28 [1·11-1·47]), pre-eclampsia (1·42 [1·25-1·61]), placental abruption (1·32 [1·22-1·44]), venous thromboembolism (2·19 [1·73-2·78]), antenatal anxiety (4·25 [2·59-6·99]), and depression (4·09 [3·27-5·11]). No significant associations were found for termination of pregnancy or chorioamnionitis. The risk of complications increased with the number of coexisting conditions. Maternal MLTCs were associated with increased risk of antenatal complications. These findings highlight the urgent need for integrated care pathways and targeted risk assessment for pregnant women with MLTCs. Medical Research Council, National Institute for Health and Care Research, Economic and Social Research Council, Engineering and Physical Sciences Research Council.