CHICAGO – Researchers at the University of Chicago say a new study indicates consumers who frequently watch pornography are more likely to have extramarital affairs than their more conservative peers.

“More than a Dalliance? Pornography Consumption and Extramarital Sex Attitudes Among Married U.S. Adults,” published in the scholarly journal Psychology of Popular Media Culture, drew its data from interviews of 551 married American adults who participated in the General Social Survey. The survey is believed to be the only national survey gathered firsthand via personal interviews about social beliefs.

Among the questions researchers asked survey subjects were “Have you seen an X-rated movie in the past year?” and “What is your opinion about a married person having sexual relations with someone other than the marriage partner?”

According to researchers Paul Wright, Robert Tokunaga and Soyoung Bae, responses indicated a correlation between porn viewing and the perception that casual, extramarital sex is “normative and rewarding.”

“Pornography consumption was associated with more positive subsequent extramarital sex attitudes,” the researchers noted in the journal article. “If pornography consumption leads to more positive extramarital sex attitudes as the results of the panels suggest, pornography consumption may be a contributing factor in some divorces via extramarital sex behaviour.”

On the other hand, researchers conceded, online pornography viewing may be no more than a symptom of other problems in the marriage.

On average, one million divorces occur annually in the U.S. In 2003, a survey of members of the American Academy of Matrimonial Lawyers discovered two-thirds of the 350 lawyers polled considered online pornography a significant cause of the divorce cases they litigated.