
In this study from Mexico, the incidence of preterm delivery was higher among patients with inadequate asthma control during the first part of pregnancy (11.4%) compared with patients with adequate asthma control (6.3%).
Patients who were hospitalized for asthma during pregnancy had a higher incidence of preterm delivery (16.4%) compared with asthmatic women without a history of hospitalization (7.6%).
The authors concluded that there is a substantial risk for preterm delivery caused by poorly controlled maternal asthma.
References:
Asthma control during pregnancy and the risk of preterm delivery or impaired fetal growth. Bakhireva LN, Schatz M, Jones KL, Chambers CD. Ann Allergy Asthma Immunol. 2008 Aug;101(2):137-43.
First-trimester asthma exacerbations may lead to birth defects
Asthma exacerbations during pregnancy can be reduced with a FENO-based treatment algorithm - number needed to treat was 6 (Lancet, 2011).
Maternal Asthma Medication Use and the Risk of Selected Birth Defects. Pediatrics, 2012.
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