Chemical Exposures Delaying Pregnancy


Exposure to chemicals is not just a concern for pregnant women and their developing child, but may play a significant role in the ability of couples to get pregnant in the first place. And men’s exposures, a new study shows, are of particular importance. The study was published in Environmental Health Perspectives on Dec. 20, 2012, and shows that couples exposed to what are known as persistent organic pollutants—or toxic chemicals in the environment—took 20% longer to become pregnant.

Some 501 couples in their 20s and 30s from Michigan and Texas looking to get pregnant were recruited and followed for the study. Researchers took blood and urine samples from participants as they were trying to conceive and assessed samples for 63 organic pollutants including, as noted in Environmental Health News, “nine pesticides, one polybrominated biphenyl (PBB), 10 polybrominated diphenyl ethers (PBDEs), 36 polychlorinated biphenyls (PCBs), and seven perfluorochemicals (PFCs).” Other factors were taken into account as well, including smoking, exercise and degree of sexual activity.

Over the study’s duration, 347 couples became pregnant while 154 did not become pregnant or left the study. It was found that men’s chemical exposures were more significant for delaying pregnancy outcomes than women’s. There were 12 toxic exposures that led to a 17-29% decreased fecundity in men including DDE—a cancer-causing toxin similar to the pesticide DDT—and PCBs 138, 156, 157, 167, 170, 172 and 209. In women, fecundity was delayed 18-21% with increased concentrations of five chemicals, including PCB 118,167 and 209 and PFOSAs—a component of Scotchgard stain- and water-repellant which accumulates in the human body and in wildlife and produces severe birth defects in lab animals. The chemical was phased out beginning in 2000, but human exposure continues.

And the chemical concentrations found to produce these impacts on couples’ ability to get pregnant were lower than averages found in the U.S. population as reported by the Centers for Disease Control.

The study lends further validation to previous findings connecting exposure to persistent organic pollutants to decreased fertility and underscores the importance of including men in such studies—and beginning such studies prior to conception. Writes Environmental Health News: “This study is one of the first to show that men’s chemical exposures are just as important—if not stronger—than women’s in determining fertility issues.”