Air pollution may put pregnant women at risk for complications during delivery

Air pollution may be toxic to pregnant women and put them at risk for complications during delivery, such as preeclampsia, according to a study from the University of Florida.

Comparing air pollution data from the Environmental Protection Agency and researchers' birth data revealed that significant exposure to four air pollutants puts pregnant women at a higher risk for high blood pressure disorder during their pregnancy.

They include two specific types of fine and coarse particulate matter - like acids, dust, metals and soil particles - which are released from industries and forest fires and can form when air gases react with one another. Other air pollutants to watch out for are sulfur dioxide, which is produced from power plants and industries, and carbon monoxide, which commonly comes from car exhaust.

About 10 percent of pregnancies are affected by hypertensive disorders, but despite their harmful implications for both mother and child, their root cause is still unknown. These conditions include gestational hypertension, preeclampsia and eclampsia which is life threatening.

Dr. Xiaohui Xu, an assistant professor of epidemiology in the colleges of Public Health and Health Professions and Medicine, said in a press release that because of these risk factors, more research is necessary.

The study, published in the Journal of Epidemiology & Community Health, sampled more than 22,000 pregnant women from Jacksonville, Fla., from 2004-2005, and examined environmental pollution levels using EPA data. Women excluded from the study had chronic hypertension, gave birth to premature babies or had complications during delivery. Controls for socioeconomic status, exposure to pollutants and women smokers were established.

Results showed that 4.7 percent of women developed a hypertensive disorder during pregnancy. There was added risk for developing one of these conditions if the women were exposed to the air pollutants within the first two trimesters of pregnancy. But Xu thinks that when a pregnant woman is exposed to air pollution - either in the late or early stages - is not important. Exposure at any point during the pregnancy term has impacts, he said. 

While the researchers note that more studies are necessary to make these results conclusive, Xu and colleagues believe more air pollution control is a step in the right direction, and that these toxins likely have some affect on a pregnant woman's blood pressure.