Temporal changes in pre‐existing health conditions five years prior to pregnancy in British Columbia, Canada, 2000–2019

Abstract

AbstractBackgroundPre‐existing health conditions increase the risk of obstetric complications during pregnancy and birth. However, the prevalence and recent changes in the frequency of pre‐existing health conditions in the childbearing population remain unknown.ObjectivesTo estimate the temporal changes in the prevalence of pre‐existing health conditions among pregnant women in British Columbia, Canada.MethodsWe carried out a population‐based cross‐sectional study of 825,203 deliveries in BC between 2000 and 2019 and examined 17 categories of physical and psychiatric health conditions recorded within 5 years before childbirth. We also undertook age‐period‐cohort analyses to evaluate temporal changes in pre‐existing health conditions.ResultsThe prevalence of any pre‐existing health condition was 26.2% (n = 216,214) with overall trends remaining stable during the study period. Between 2000 and 2019, the prevalence rates of anxiety (5.6%–9.6%), bipolar (1.6%–3.4%), psychosis (0.7%–0.8%), and eating disorders (0.2%–0.3%) increased. The prevalence of hypertension increased sharply from 0.06% in 2000 to 0.3% in 2019. Diabetes mellitus and stroke rates increased, as did the prevalence of systemic lupus, multiple sclerosis, and chronic kidney disease. Advanced maternal age was strongly associated with both psychiatric and circulatory/metabolic conditions. A strong birth cohort effect was evident, with rates of psychiatric conditions increasing among women born after 1985.ConclusionsIn British Columbia, Canada, 1 in 4 mothers had a pre‐existing health condition 5 years prior to pregnancy. These findings underscore the need for multi‐disciplinary care for women with pre‐existing health conditions to improve maternal, foetal, and infant health.