Air Pollution Increases Hypertension Risk in Pregnant Women

Air pollution increases risk of high blood pressure in pregnant women, a new study has found.

The study, conducted by researchers at University of Florida, was based on data from 22,000 women.

Previous research has shown that air pollution can increase risk of preeclampsia- a condition where the pregnant woman develops high blood pressure. Air pollution is also associated with increased risk of a still birth.

"Fetal development is very sensitive to environmental factors," said Dr. Xiaohui Xu, an assistant professor of epidemiology in the colleges of Public Health and Health Professions and Medicine, according to a news release. "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."

Air pollution generally has fine and coarse particulates, sulfur dioxide and carbon monoxide, researchers said.

Sulfur dioxide is released by industries while carbon monoxide comes from exhausts of motor vehicles. Particulate matters include dust, metals and compounds formed when gasses in the air react with other, according to Environment Protection Agency.

Data for the study came from 22,000 pregnant women who gave birth between 2004 and 2005 in Jacksonville, Fla. Researchers collected data on air pollution levels from EPA.

The team didn't include women who had history of hypertension, had previously delivered premature children or had complications during delivery.

Researchers estimated the level of air pollution that women might have experienced during pregnancy.

In the study group, 4.7 percent of women developed hypertension during pregnancy.

According to Xu, exposure to air pollutants during the first few months of pregnancy increased women's odds of developing high blood pressure.

The link between hypertension and air pollution remained even after researchers accounted for other risk factors such as socioeconomic status or exposure to cigarette smoke.

The study is published in the Journal of Epidemiology & Community Health.