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Systematic Review of the Safety of Regular Preventive Asthma Medications During Pregnancy

Objective: To review the safety of regular preventive asthma medications during pregnancy. Data Sources: The following databases were searched from inception to February 2011: Ovid MEDLINE, PubMed, Cochrane Library, EMBASE and CINAHL Plus. Study Selection and Data Extraction: The search was limited to human studies published in the English language. Titles of all articles were screened for relevance. Abstracts of relevant articles were scrutinized to confirm relevance before obtaining full text. Data Synthesis: Selected articles were read by 2 authors and the accuracy of the data extracted was confirmed. Results: Thirty-three articles were included in the final review. Small sample size, missing data, inadequate control for confounding factors, and poor documentation of dosage range were common limitations of the studies reviewed. The use of inhaled corticosteroids, cromolyns, and long-acting β2 agonists during pregnancy was not associated with any particular adverse event, although the fluticasone/salmeterol combination has been associated with poor outcomes in postmarketing studies. Congenital malformations have been reported with leukotriene receptor antagonist exposure during pregnancy, but those women also had exposure to other medications, including oral corticosteroids. Conclusions: Some negative outcomes of preventive asthma medications have been reported, although their direct link with medication use is inconclusive. Selection of preventive medications for asthma management during pregnancy should be based on an assessment of the risks and benefits of medication use versus the risks of poorly controlled asthma.