After years together, many married couples complain that their sex lives fizzle. But research has found that some couples enjoy sex more often. Their secret? It turns out that these couples divvy up the housework along traditional gender lines—with men paying the bills, handling yard work and maintaining the car while wives cooked, cleaned and shopped for the home. Couples who shared the housework load equally enjoyed sex less often.  

For the study, which was published in the American Sociological Review, researchers at the University of Washington mined data from a national survey of about 4,500 U.S. heterosexual married couples from 1992 to 1994.

“In particular, it seems that the gender identities husbands and wives express through the chores they do also help structure sexual behavior,” says Julie Brines, PhD, an associate professor at the university.

But guys: Don’t think this is an excuse for you not to do “women’s work.” As another university researcher warned, this could increase domestic conflicts and make women less satisfied being married.

“Marriage today isn’t what it was 30 or 40 years ago,” Brines sums up, “but there are some things that remain important. Sex and housework are still key aspects of sharing a life, and both are related to marital satisfaction and how spouses express their gender identity.”

Now, who’s going to clean up that mess in the living room?