Published Online: August 5, 2013
Asthma is fairly common in women of reproductive age and complicates about 7-10% of pregnancies in the US. Mothers with asthma are known to have increased risk of pregnancy complications including preterm birth and growth restriction in their newborns. However, other serious newborn complications have not been well studied in relation to maternal asthma.
In an original research article published in The Journal of Allergy and Clinical Immunology (JACI), Mendola et al. hypothesized that the newborns of asthmatic mothers would experience more complications compared to newborns whose mothers did not have asthma. The study team analyzed data from a large contemporary obstetric cohort, the Consortium on Safe Labor (2002-2008), which included electronic medical records for mothers and babies from 223,512 singleton deliveries at ≥ 23 weeks of gestation. Newborns of mothers with asthma (n=17,044) were compared to newborns of non-asthmatic mothers for potential differences in gestational week at delivery, birthweight, and a number of newborn complications.
As expected, the study found an increased risk for preterm birth and for babies born small for gestational age related to maternal asthma. With data from such a large number of deliveries, the authors were able to examine risk for early delivery at each week of gestation—a novel aspect of the study. They found that preterm delivery was associated with maternal asthma for each week after 33 completed weeks of gestation, but not earlier. Maternal asthma also increased the risk for neonatal intensive care unit (NICU) admission; jaundice; and breathing complications including respiratory distress syndrome, transient tachypnea of the newborn, and asphyxia. These findings were present even if babies were born at term (delivery ≥ 37 weeks). Infants who were born at term had additional increased risk for intracerebral hemorrhage and anemia. However, maternal asthma did not increase risk for perinatal death, infections such as sepsis or pneumonia, or other uncommon complications.
In summary, this study highlights a connection between maternal asthma and neonatal health, showing that maternal asthma is associated with a broader set of neonatal complications than previously thought. Future research can build on this work by exploring whether efforts to control maternal asthma can mitigate newborn risks.
The Journal of Allergy and Clinical Immunology (JACI) is the official scientific journal of the AAAAI, and is the most-cited journal in the field of allergy and clinical immunology.