But McLaughlin is cautious not to over-interpret the findings. "The major strength of the study is that it is a world-class nationwide longitudinal study of pregnant women. Do I believe that PFCs really affect time to pregnancy? It remains to be seen."
Dr. Richard Paulson, chief of the Division of Reproductive Endocrinology and Infertility at the University of Southern California, agrees.
"The study can only show an association and not causation," he says. "The time to pregnancy is dependent on so many different factors that it would be impossible to control for all of them."
In the paper, the authors admit that they did not have information on some other important factors that affect fertility, including the frequency and timing of intercourse and sperm quality.
"Nevertheless, it is provocative to have an association between these chemicals and time to pregnancy," Paulson says. "We should be anxiously awaiting further confirmation of these preliminary results in future, larger, hopefully prospective, studies."
The jury is still out on what impact, if any, PFCs have on fertility. Even so, several years ago the U.S. Environmental and Protection Agency negotiated with 3M, the sole manufacturer of PFOS, to stop producing the chemical. Since that time, however, PFOA continues to be used and the EPA does not have enough information to recommend that consumers stop using products that contain it. But they have created a voluntary program for companies to reduce and ultimately eliminate PFOA emissions and product content by 2015.
Landrigan, however, says a more aggressive approach is needed.
"PFCs aren't banned but there are a couple of common sense things people can do to reduce their exposure," he says. "There's a lot we don't know about toxicity but we can use common sense.
"So stop using Teflon frying pans, don't use scotch guard that contains these compounds and, whenever possible, families should think twice about using plastic to store food and should go back to glass."
Michelle Schlief contributed to this report.