Asthma in Pregnancy

Abstract

Asthma is a chronic inflammatory respiratory illness manifesting with intermittent or persistent symptoms and is frequently encountered in pregnant women, most of whom have been diagnosed prior to conception. The degree of control over the illness in pregnancy often changes compared to the pre-pregnant state. Some of this change is likely mediated by the modified physiologic and immunologic state of pregnancy. Another contributor is decreased treatment, a well-intentioned but erroneous approach stemming from concern in a proportion of mothers and health-care providers about adverse effects of medications on the fetus. Poorly controlled asthma has the potential to cause morbidity in the mother and fetus, the latter being particularly vulnerable to the effects of hypoxia. Effective treatments exist to reduce morbidity and mortality from asthma, and management algorithms emphasize maintenance of good control of symptoms. Key pharmacologic agents used to treat asthma in the general population, particularly bronchodilators and inhaled corticosteroids, have established safety profiles for use in pregnant women. While some studies have shown associations between asthma medications and adverse perinatal events and congenital defects, the confounding effect of underlying asthma severity remains a significant obstacle to drawing firm conclusions. The overwhelming consensus is that the risk of leaving asthma untreated is greater than any risk conferred by most pharmacologic interventions. Pregnant women with asthma should be assessed regularly throughout pregnancy, and medications should be optimized to prevent exacerbations and minimize risks of fetal hypoxia. Exacerbations should be treated aggressively, and concomitantly, fetal well-being must be monitored closely.