SAN DIEGO, CA – An extensive review of pregnancies over the course of more than three decades shows that women with poorly-managed asthma are at an increased risk of having a low-birth weight baby, a premature baby and other pregnancy complications, such as preeclampsia. The new study was recently published in the British Journal of Obstetrics and Gynecology.
Christina Chambers, PhD, MPH, a professor of pediatrics at the University of California, San Diego and program director of the California Teratogen Information Service (CTIS) Pregnancy Health Information Line, a California non-profit that educates the public about exposures during pregnancy and breastfeeding, was part of the team of seven researchers who reviewed data involving more than one million women between 1975 and 2009.
“The findings are significant and call for women with asthma to be more closely-monitored during pregnancy,” explained Dr. Chambers. “It would be advisable for women on regular medications for asthma or having frequent symptoms to be monitored at least monthly during the course of their pregnancies,”
More specifically, the study found that the infants of women with asthma were likely to weigh an average of 0.2 lbs. less at birth compared to babies of mothers without asthma. Mothers with poorly-controlled asthma were also at a 25% increased risk of pre-term birth and 50% increased risk of developing preeclampsia, a condition in which high blood pressure develops during pregnancy.
“The study does not clarify the mechanism of the increased risk,” said Michael Schatz, MD, asthma specialist at Kaiser Permanente Medical Center in San Diego and also a co-author on the study. “Most information suggests it is only uncontrolled asthma that increases the risk,” he added. “But more information on other potential factors, such as asthma medications, is needed.”
CTIS’ national affiliate, the Organization of Teratology Information Specialists (OTIS), in collaboration with the American Academy of Allergy, Asthma & Immunology, recently launched an extensive study regarding asthma medications in pregnancy. It is an observational study where medications and asthma control of pregnant women will be carefully monitored and related to pregnancy outcomes. OTIS is seeking both pregnant women with asthma and pregnant women who do not have asthma. To learn more about the study or to volunteer please visit OTISPregnancy.org.



