Pollutants affect in vitro fertilization

HERSHEY, Pa., April 12 (UPI) -- U.S. medical fertility scientists say they've found exposure to nitrogen dioxide and other air pollutants can affect the success of in vitro fertilization.

The team said it examined the outcomes of the first pregnancy attempts of 7,403 women undergoing IVF at Penn State University's Hershey Medical Center, Shady Grove Fertility of Rockville, Md.; and Columbia University College of Physicians and Surgeons in New York. They conducted their observations over a seven-year period from 2000 to 2007.

"Numerous studies have consistently shown a relationship between air pollution and human health, ranging from mortality, cardiovascular disease and other chronic conditions," said Penn State Professor Duanping Liao. "In the process of searching for the mechanisms responsible for the … associations, we, and others, have reported significant links between air pollution and inflammation and increased blood-clotting. These intermediate factors are also associated with reproductive health."

The researchers said their findings may be useful in studying the adverse effects of air pollution on human reproduction in general.

"Since IVF is a well-controlled and highly timed process, we have a much better handle on the assessment of the time of exposures to elevated air pollutants in relationship to fertilization, pregnancy and delivery," Liao said. The findings may provide an ideal situation to investigate the potential health effects of air quality on human reproduction, he said.

The study appears in the journal Human Reproduction.