Severe asthma exacerbations during pregnancy

To estimate the frequency of severe asthma exacerbations in pregnant women and to estimate whether there is an association with adverse perinatal outcomes. Asthma exacerbations were evaluated in 146 women who were enrolled in a prospective cohort study of asthma and pregnancy. A severe exacerbation was defined as a hospital admission, emergency department presentation, or unscheduled doctor visit for asthma or a course of oral corticosteroids. Women were classified as having mild (n = 63), moderate (n = 34), or severe (n = 49) asthma. Severe exacerbations occurred in 8% (95% confidence interval [CI] 1.3-14.6%) of women with mild asthma, 47% (95% CI 30.3-63.8%) of women with moderate asthma, and 65% (95% CI 52-78.6%) of women with severe asthma at a mean gestational age of 25.1 +/- 0.9 (range 9-39) weeks of gestation. Among women who had severe exacerbations, there were 2 male stillbirths (P = .102) and a significantly increased rate of male low birth weight (P = .03). Maternal age, lung function, body mass index, gravidity, and parity were not different between women who did or those who did not have a severe exacerbation. Maternal pregnancy weight gain was significantly lower in women who had a severe exacerbation (P = .039). Forty-three percent of severe exacerbations occurred in winter, 34% were associated with self-reported viral infection, and 29% with nonadherence to inhaled corticosteroid medication. The exacerbation rate among pregnant women with asthma is high and associated with poor outcomes for the male fetus. Improvements in asthma management to prevent severe exacerbations may lead to a better outcome for both mother and baby. II-2.