Published online: January 22, 2020
The relationship between maternal asthma and perinatal outcomes is not well understood. Several studies have suggested an increased risk of adverse outcomes among pregnancies of women with asthma. However, estimates of these effects have been inconsistent, possibly due to differences in definition of asthma severity or control, or timing of exposure evaluation.
In an article recently published in The Journal of Allergy and Clinical Immunology: In Practice (JACI), Yland and colleagues evaluated the relationships among maternal asthma, its severity and control, and several perinatal outcomes. This study was conducted within two large US healthcare administrative databases. Identification of asthma, and its severity and control, was based on diagnosis and treatment codes and medication dispensation claims. The authors classified asthma severity based on the Global Initiative for Asthma (GINA) stepwise treatment guidelines. Control was based on short-acting beta agonist dispensations and exacerbations and was evaluated during etiologically relevant periods. For example, control was measured in the first trimester for evaluation of congenital malformations, but in the 90 days before delivery for evaluation of preterm birth. The authors evaluated the risks of stillbirth, spontaneous abortion, preterm birth, small for gestational age (SGA), neonatal intensive care unit (NICU) admission, and congenital malformations, comparing pregnancies with differing asthma disease status.
In this large, nationally representative study, the authors identified almost 200,000 pregnancies complicated by asthma from 2000-2015. There were no consistent associations between asthma diagnosis, severity, or control, and stillbirth, abortions, or malformations. However, the authors observed an association between asthma severity and SGA; and between exacerbations late in pregnancy and preterm delivery and NICU admission. The apparent effect of exacerbations persisted among women with mild asthma. These findings suggest that attaining optimal asthma control during pregnancy is important even for patients with mild asthma, as it has the potential to reduce the risk of neonatal complications.
The Journal of Allergy and Clinical Immunology: In Practice is an official journal of the AAAAI, focusing on practical information for the practicing clinician.