Asthma Symptoms, Severity, and Drug Therapy

Abstract

In Brief OBJECTIVE To prospectively examine in pregnant women whether asthma or asthma therapy influenced preterm delivery, intrauterine grown restriction (IUGR), or birthweight. METHODS We enrolled 873 pregnant women with a history of asthma, of whom 778 experienced asthma symptoms or took medication, and 1333 women with no asthma history, including 884 women with neither asthma diagnosis nor symptoms and 449 with symptoms but no diagnosis. Asthma symptoms, medication, and severity were classified according to 2002 Global Initiative for Asthma guidelines. RESULTS Preterm delivery was not associated with asthma diagnosis, severity, or symptoms but was associated with use of controller medications, independent of symptoms, specifically oral steroids and theophylline. Gestation was reduced by 2.22 weeks in women using oral steroids daily (P = .001) and 1.11 weeks after theophylline (P = .002). We observed a 24% (5–47%) increased risk for IUGR with each increased symptom step, which increased further in symptomatic women with no asthma diagnosis (31%, 4–65%) compared with women with neither asthma nor symptoms. CONCLUSION We found no effect of asthma symptoms or severity on preterm delivery but observed increased risks associated with use of oral steroid and theophylline. Intrauterine growth restriction was associated with asthma severity, which possibly reflects a hypoxic fetal effect. Women with asthma symptoms but no diagnosis were at particular risk of undermedication and delivering IUGR infants. These observations support guidelines that advocate active management of pregnant patients with mild or moderate asthma with β2 agonists, with oral steroids added only if severity increases. Symptomatic patients without an asthma diagnosis might need to be equally managed. Asthma severity and medication use are associated with intrauterine growth restriction, gestational age, and preterm delivery; this finding supports current guidelines for managing the pregnant asthmatic patient.