Forget the proverbial seven-year itch. Not to disillusion the half million or so June brides and bridegrooms who were just married, but new research suggests that the spark may fizzle within only three years.

Researchers analyzed responses from two sets of married or cohabitating couples: one group was together for one to three years, the other for four to six years. While the researchers could not pinpoint a precise turning point - the seven-year itch, as popularized in the play and film about errant husbands, was largely a theory - they found distinct differences between the groups. "We know the earlier ones are happier," said Prof. Kelly Musick, a University of Southern California sociologist. "The initial boost that marriage seems to provide fades over time."

Research also showed that the median duration of first marriages that end in divorce remains a little more than seven years, which means that those couples will likely spend more than half their married lives less happy than they were when they cut the first slice of wedding cake. "Some folks start getting less happy at the wedding reception," said Larry Bumpass, a professor at the University of Wisconsin-Madison, who wrote the study with Professor Musick.

Is there a three-year itch? "There is not necessarily anything magical about year three," Professor Musick said. "We know that typically when marriages end in divorce, half end before seven or so years and half end after. This is the same idea."