Neonatal health of infants born to mothers with asthma

Abstract

Background: Maternal asthma is associated with serious pregnancy complications, but newborn morbidity is understudied.

Objective: We wanted to determine whether infants of asthmatic mothers have more neonatal complications.

Methods: The Consortium on Safe Labor (2002-2008), a retrospective cohort, included 223,512 singleton deliveries at ≥ 23 weeks' gestation. Newborns of mothers with asthma (n = 17,044) were compared with newborns of women without asthma by using logistic regression models with generalized estimating equations to calculate adjusted odds ratios (ORs) and 95% CIs. Electronic medical record data included gestational week at delivery, birth weight, resuscitation, neonatal intensive care unit (NICU) admission, NICU length of stay, hyperbilirubinemia, respiratory distress syndrome, apnea, sepsis, anemia, transient tachypnea of the newborn, infective pneumonia, asphyxia, intracerebral hemorrhage, seizure, cardiomyopathy, periventricular or intraventricular hemorrhage, necrotizing enterocolitis, aspiration, retinopathy of prematurity, and perinatal mortality.

Results: Preterm delivery was associated with maternal asthma for each week after 33 completed weeks of gestation and not earlier. Maternal asthma also increased the adjusted odds of small for gestational age (OR = 1.10; 95% CI, 1.05-1.16), NICU admission (OR = 1.12; 95% CI, 1.07-1.17), hyperbilirubinemia (OR = 1.09; 95% CI, 1.04-1.14), respiratory distress syndrome (OR = 1.09; 95% CI, 1.01-1.19), transient tachypnea of the newborn (OR = 1.10; 95% CI, 1.02-1.19), and asphyxia (OR = 1.34; 95% CI, 1.03-1.75). Findings persisted for term infants (≥ 37 weeks) who had additional increased odds of intracerebral hemorrhage (OR = 1.84; 95% CI, 1.11-3.03) and anemia (OR = 1.30; 95% CI, 1.04-1.62).

Conclusions: Maternal asthma was associated with prematurity and small for gestational age. Adverse neonatal outcomes, including respiratory complications, hyperbilirubinemia, and NICU admission, were increased in association with maternal asthma even among term deliveries.

Keywords: CSL; Consortium on Safe Labor; ICD-9; International Classification of Diseases, Ninth Revision; LGA; Large for gestational age; NICU; Neonatal health; Neonatal intensive care unit; OR; Odds ratio; SGA; Small for gestational age; maternal asthma; neonatal jaundice; preterm birth; respiratory distress syndrome; transient tachypnea of the newborn.

Figure 1

The odds ratios (ORs) with 95% confidence intervals of preterm birth for each gestational week for infants born to mothers with asthma compared to infants of mothers without asthma, with a fetuses-at-risk approach where each gestational age defines the cutpoint of the comparison groups.