RT Journal Article SR Electronic T1 Asthma exacerbations during pregnancy increase risk of adverse perinatal outcomes JF European Respiratory Journal JO Eur Respir J FD European Respiratory Society SP 4643 DO 10.1183/13993003.congress-2020.4643 VO 56 IS suppl 64 A1 Annelies Robijn A1 Bronwyn Brew A1 Megan Jensen A1 Gustaf Rejnö A1 Cecilia Lundholm A1 Vanessa Murphy A1 Catarina Almqvist YR 2020 UL http://erj.ersjournals.com/content/56/suppl_64/4643.abstract AB Introduction: Asthma is highly prevalent during pregnancy and has been associated with poor outcomes. The effect of asthma exacerbations on perinatal outcomes has not been studied extensively.Aim: To estimate the association between asthma exacerbations and perinatal outcomes; and whether this differs by treatment regime as a proxy for asthma severity.Methods: We included singleton births of women with asthma in Sweden from July 2006-November 2013 (N=33,829). Asthma exacerbations were defined as unplanned emergency visits/hospitalisations, or a short course of oral corticosteroids. Adjusted odds ratios (aOR) were estimated for the associations between exacerbations during pregnancy and perinatal outcomes (small for gestational age (SGA), preterm birth, birth weight and mode of delivery), stratified by treatment regime.Results: Exacerbations occurred in 1,430 (4.2%) pregnancies. Exacerbations were associated with reduced birth weight (2500-2999g vs. 3000-4000g), aOR 1.45 (95%CI 1.24-1.70), and elective (aOR 1.50, 95%CI 1.25-1.79) and emergency C-section (CS, aOR 1.35, 95%CI 1.13-1.61). Multiple exacerbations were associated with a 2.6-fold increased odds of SGA (95%CI 1.38-4.82). Amongst women treated pre-pregnancy with combination therapy (proxy for moderate-severe asthma), exacerbators were at increased odds of elective (aOR 1.69, 95%CI 1.30-2.2) and emergency (aOR 1.62, 95%CI 1.26-2.08) CS; and SGA (aOR 1.74, 95%CI 1.18-2.57) vs. non-exacerbators.Conclusion: Asthma exacerbations during pregnancy increase the risk of C-section delivery, and infants born SGA. These odds further increased with multiple exacerbations or when treated pre-pregnancy with combination therapy suggesting greater asthma severity.FootnotesCite this article as: European Respiratory Journal 2020; 56: Suppl. 64, 4643.This abstract was presented at the 2020 ERS International Congress, in session “Respiratory viruses in the "pre COVID-19" era”.This is an ERS International Congress abstract. No full-text version is available. Further material to accompany this abstract may be available at www.ers-education.org (ERS member access only).