Pregnant Asthmatic Women Can Limit Newborn Complications Using Beta2 Agonists

Pregnant women with asthma can limit newborn complications if they actively manage their asthma with Beta2 agonists, commonly known as bronchodilaters, Yale researchers report in the October issue of Obstetrics and Gynecology.

Principal Investigator, Michael Bracken and his team studied 2,205 pregnant women from 56 obstetrical practices and 15 clinics associated with six hospitals in Connecticut and Massachusetts. Women were interviewed soon after their first prenatal visit at three selected times throughout pregnancy and soon after delivery. The team collected information about respiratory symptoms, medication use, hospitalizations and emergency room visits. Medical records provided information on pregnancy outcomes.

“These findings support current practice guidelines that pregnant women with mild or moderate asthma be managed with Beta2 agonists, and that oral steroids should only be prescribed if asthma severity increases,” said Michael Bracken, the Susan Dwight Bliss Professor of Epidemiology and professor of neurology and obstetrics and gynecology at Yale School of Medicine.

Previous studies showed that use of oral steroids and theophylline, a smooth muscle relaxant, to manage asthmatic women may increase the risk of preterm delivery.

Bracken noted another important finding: women who have asthma symptoms, but are not diagnosed as having the disease, are very likely to be under-medicated and to have up to three times the risk of delivering a baby with fetal growth reduction. It is speculated that this developmental issue may be due to breathlessness in the mother, resulting in reduced oxygen supply to the fetus.

“This previously unidentified group of high risk mothers may need more active management of their symptoms to reduce pregnancy complication risks,” said Bracken.

Other authors on the study included Elizabeth Triche, Kathleen Belanger and Brian Leaderer, all from the Yale Center for Perinatal, Pediatric and Environmental Epidemiology and the Department of Epidemiology and Public Health at Yale; Audrey Saftlas from the University of Iowa College of Public Health and William Beckett from the University of Rochester School of Medicine and Dentistry.

The study was funded by grants from the Institute of Drug Abuse and the Institute of Allergy and Infectious Disease of the National Institutes of Heath.