Effect of pregnancy on asthma control: a cohort study in rural Sri Lanka

Introduction: Effect of poor control of asthma-the most common chronic disease complicating pregnancy-in rural populations is not adequately studied. Objective: To assess the symptom profile, progression and outcomes of asthma complicating pregnancy. Methods: A community-based cohort study was conducted among all pregnant women registered in the maternal care programme in July-September 2019 in Anuradhapura, Sri Lanka. Full clinical assessment was done in 1st(T1) and 2nd(T2) trimesters and pregnancy outcome data were obtained from labour rooms. Results: Of the 3374 pregnant women assessed, the prevalence of self-reported physician-diagnosed asthma was 6.6%(n=223). The prevalence of wheeze among asthmatics reduced (p<0.01) from pre-pregnancy (last 3 months before pregnancy) (67.0%;95%CI 60.3-73.1) to T1 (46.7%;95%CI 39.6-53.2) and T2 (47.7%;95%CI 37.9-57.5). The frequency of wheeze increased in 53(25.4%) and 22(23.4%) asthma patients and new-onset wheeze was reported by 6(8.1%) and 12(16.2%) in T1 and T2. Pregnant women who sought medical care for asthma at the private sector had a lower likelihood of developing new-onset wheeze in T1(OR=0.51; 95%CI 0.44-0.59; p=0.03). The prevalence of non-cardiac dyspnoea in pre-pregnancy among asthmatics (20.4%), increased(p=0.11) in T1 (23.3%) and T2 (28.3%;95%CI 20.0-37.9). Incidence of miscarriage, preterm delivery and low birth weight (LBW) among asthmatics was 9.5% (95%CI 6.0-14.1), 11.1% (95%CI 7.0-16.5) and 16.0% (95%CI 11.1-22.1). Wheezing in T2 significantly associated with LBW (OR=3.2, 95%CI 1.04-9.6; p=0.04). Conclusion: Significant changes in asthma symptom control during pregnancy and adverse pregnancy outcomes were observed in this pregnancy cohort in rural Sri Lanka.