Maternal multimorbidity and preterm birth in Scotland: an observational record-linkage study

Abstract

Background Multimorbidity is common in women across the life course. Preterm birth is the single biggest cause of neonatal mortality and morbidity. We aim to estimate the prevalence of multimorbidity in pregnant women and to examine the association between maternal multimorbidity and PTB. Methods This is a retrospective cohort study using electronic health records from the Scottish Morbidity Records. All pregnancies among women aged 15 to 49 with a conception date between 1 January 2014 and 31 December 2018 were included. Multimorbidity was defined as the presence of two or more pre-existing long-term physical or mental health conditions, and complex multimorbidity as the presence of four or more. It was calculated at the time of conception using a predefined list of 79 conditions published by the MuM-PreDiCT consortium. PTB was defined as babies born alive between 24 and less than 37 completed weeks of gestation. We used Generalised Estimating Equations adjusted for maternal age, socioeconomic status, number of previous pregnancies, BMI, and smoking history to estimate the effect of maternal pre-existing multimorbidity. Absolut rates are reported in the results and tables, whilst Odds Ratios (ORs) are adjusted (aOR). Results Thirty thousand five hundred fifty-seven singleton births from 27,711 pregnant women were included in the analysis. The prevalence of pre-existing multimorbidity and complex multimorbidity was 16.8% (95% CI: 16.4–17.2) and 3.6% (95% CI: 3.3–3.8), respectively. The prevalence of multimorbidity in the youngest age group was 10.2%(95% CI: 8.8–11.6), while in those 40 to 44, it was 21.4% (95% CI: 18.4–24.4), and in the 45 to 49 age group, it was 20% (95% CI: 8.9–31.1). In women without multimorbidity, the prevalence of PTB was 6.7%; it was 11.6% in women with multimorbidity and 15.6% in women with complex multimorbidity. After adjusting for maternal age, socioeconomic status, number of previous pregnancies, Body Mass Index (BMI), and smoking, multimorbidity was associated with higher odds of PTB (aOR = 1.64, 95% CI: 1.48–1.82). Conclusions Multimorbidity at the time of conception was present in one in six women and was associated with an increased risk of preterm birth. Multimorbidity presents a significant health burden to women and their offspring. Routine and comprehensive evaluation of women with multimorbidity before and during pregnancy is urgently needed.

Burden of multiple high-risk factors in pregnancy before and after the universal two-child policy in Chinese women: An observational study

“…Furthermore, respiratory diseases were strongly associated with cardiovascular diseases, urinary diseases, and immune diseases, which are all chronic diseases comorbid with pregnancy. This aligns with the growing research interest in maternal multimorbidity that presents a significant health burden to women, as the disease profile in this population changes over time [ 13 , 14 , 54 ]. By identifying these core factors in MHFP, our study provides essential information for health care providers, highlighting which factors should be prioritised in the development of effective prevention and management strategies for pregnant women.…”

“…First, the higher burden of certain chronic conditions, such as obesity, hypertension, diabetes, and heart diseases, has increased the proportion of HRP women accompanied with related pregnancy comorbidities and complications [ 40 ]. Accordingly, a significant burden of multimorbidity among pregnancy women was found in several contexts, with an estimated prevalence of 10.2% in UK [ 14 ], 6.3% in Japan [ 16 ], and 2.3% in China [ 17 ]. Second, the easing of childbirth policy has directly led to the increased proportion of multiparous pregnancies [ 6 , 41 ].…”

“…Our findings imply that there is a need to shift the focus of research from single risk factors to a broader spectrum of factors and identify their cross-associations. For example, Periyasamy and colleagues have conducted research on HRP considering a broad profile of multiple factors based on a population from India National Family Health Survey [ 18 ], while the MuM-PreDiCT Group has explored intervention strategies or programmes to improve maternity care for pregnant women with two or more health conditions [ 13 , 14 , 54 ]. Transnational and multidisciplinary studies could compare these findings with international data, which could provide a broader understanding of how policy changes and socioeconomic factors impact maternal health globally.…”

“…Corresponding strategies and measures should correspond to the perceived needs and the policy change. This recommendation can be implemented by paying special attention to women with advanced maternal age who also have a higher rate of caesarean delivery in previous pregnencies [ 6 ]; starting maternal health care before pregnancy, thereby complying with the increased burden of chronic conditions [ 14 ]; and shifting the vertically structured health care system towards horizontal frameworks beyond current HRP management based on individual risk factors. Notably, the high prevalence of HRP after the policy implementation (73.26% in this study) may cause increased risk of mental health disorders (such as stress and anxiety) [ 60 ].…”

“…Recent studies have improved our understanding of some specific factors in pregnancy and their related outcomes, such as gestational diabetes mellitus (GDM) and hypertensive disorders [ 9 – 12 ], with recent research attention being diverted towards the coexistence of multiple high-risk factors in pregnancy (MHFP) [ 13 – 18 ]. For example, a cross-sectional study among the UK population estimated that the prevalence of coexisting multiple chronic conditions ranged from 19.8% to 46.2% in pregnant women and was associated with higher odds of preterm birth (adjusted odds ratio (aOR) = 1.64; 95% confidence interval (CI) = 1.48–1.82) [ 13 , 14 ]. Similarly, maternal multimorbidity was found to associate with preterm birth, low birthweight, and small for gestational age according to a study conducted in Japan [ 16 ].…”