The Association of Periconception Asthma Medication Discontinuation with Adverse Obstetric Outcomes.

OBJECTIVE: This study aimed to investigate asthma medication reduction in the periconceptional period as it relates to asthma status and adverse outcomes in pregnancy. STUDY DESIGN: In a prospective cohort study, self-reported current and past asthma medications were collected and analyzes compared measures of asthma status in women who discontinued asthma medication in the 6 months prior to enrollment ("step-down") versus those who did not ("no change"). Evaluation of asthma was done at three study visits (one per trimester) and by daily diaries, including measures of lung function (percent predicted forced expiratory volume in 1 and 6 s [%FEV1, %FEV6], peak expiratory flow [%PEF], forced vital capacity [%FVC], FEV1 to FVC ratio [FEV1/FVC]), lung inflammation (fractional exhaled nitric oxide [FeNO], ppb), rate of asthma symptoms (activity limitation, night symptoms, rescue inhaler use, wheeze, shortness of breath, cough, chest tightness, chest pain), and rate of asthma exacerbations. Adverse pregnancy outcomes were also evaluated. Adjusted regression analyses examined whether adverse outcomes differed by periconceptional asthma medication changes. RESULTS: Of 279 participants included in analyses, 135 (48.4%) did not change asthma medication in the periconceptional period, whereas 144 (51.6%) reported a step down in medication. Those in the step-down group were more likely to have milder disease (88 [61.1%] in the step-down vs. 74 [54.8%] in the no change group), exhibited less activity limitation (rate ratio [RR]: 0.68, 95% confidence interval [CI]: 0.47-0.98), and experienced fewer asthma attacks (RR: 0.53, 95% CI: 0.34-0.84) during pregnancy. The step-down group had a nonsignificant increase in overall odds of experiencing an adverse pregnancy outcome (odds ratio: 1.62, 95% CI: 0.97-2.72). CONCLUSION: Over half of women with asthma reduce asthma medication in the periconceptional period. Although these women typically have milder disease, a step down in medication may be associated with an increased risk of adverse pregnancy outcomes. KEY POINTS: · Many women reduce their asthma medication in pregnancy.. · Reduction is more common among those with mild disease.. · Medication reduction may lead to adverse pregnancy outcomes..