Everybody knows by now that cigarette smoke is bad news for pregnant women and their unborn child. But a new University of Florida study finds that stepping outside for a breath of fresh air may not be the answer.
The UF researchers found that outside air may be just as toxic to pregnant women —if not more so — as cigarette smoke, increasing a mother-to-be’s risk of developing deadly complications such as preeclampsia.
“Fetal development is very sensitive to environmental factors,” said Xiaohui Xu, M.D., Ph.D., an assistant professor of epidemiology in the colleges of Public Health and Health Professions and Medicine. “That is why we wanted to do this research. Hypertension (high blood pressure), in particular, is associated with increased morbidity and mortality, causing a lot of problems for the mother and fetus, including preterm delivery.”
The researchers compared birth data with Environmental Protection Agency estimates of air pollution, finding that heavy exposure to four air pollutants led to a significantly increased risk for developing a high blood pressure disorder during pregnancy. The research was published in the January issue of the Journal of Epidemiology & Community Health.
The pollutants include two specific types of fine and coarse particulate matter, carbon monoxide and sulfur dioxide. According to the EPA, particulate matter includes acids, dust, metals and soil particles. These inhalable particles are released from industries and forest fires and can form when gases react with each other in the air. Sulfur dioxide is emitted from power plants and industries. Most carbon monoxide is produced by car exhaust.
To gain a better understanding of how environmental factors may play a role in increasing the risk of developing hypertension during pregnancy, the researchers examined data from women who gave birth in Jacksonville, Fla., between 2004 and 2005 and environmental data from their communities. The sample included more than 22,000 pregnant women.
They gauged how much pollution the women were exposed to throughout their pregnancies using data the EPA gathered daily to measure the levels of several pollutants.
Among the sample, 4.7 percent developed a hypertensive disorder during pregnancy. Exposure to air pollutants throughout the first two trimesters of pregnancy increased women’s risk of developing one of these conditions, Xu said.
On the basis of these findings, the researchers say more air pollution control is necessary to prevent dangerous complications in pregnant women and babies. Although more studies are needed, the researchers hypothesize that exposure to air pollution during pregnancy may affect a woman’s normal pattern of blood pressure.