If you’re a single parent, handling all the housework and childcare responsibilities on your own, you might expect to do more work at home than women with a partner to pick up the slack. But married women actually do more domestic work than their single mom counterparts—provided their partner is a man.
Women married to men spend more time on housework than single moms, according to a new study from sociologists at the University of Maryland, University of Texas, and University of Southern California. Why? The researchers say that married moms are more likely to “perform gender” in their relationships. “Married mothers increase housework in part to meet expectations about home-cooked meals, clean clothes, and well-kept houses—behavior integral to contemporary definitions of appropriate behavior for wives and mothers,” authors Joanna Pepin, Liana C. Sayer, and Lynne M. Casper write.
Adjusted for differences in employment, education, race, and number of children or other extended family members at home, married women spend an average of 2.95 hours daily on housework, compared to 2.41 hours for unmarried women—a difference of about 32 minutes every day. Married mothers report spending 10 minutes less daily on leisure and 13 minutes less daily on sleep—small differences, but ones that add up over a week. The findings hold true whether the married woman works full-time or is a stay-at-home mom, as a married woman’s time becomes a “shared household resource.”
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“Marriage remains a gendered institution that ratchets up the demand for housework and childcare through essentialist beliefs that women are naturally focused on home and hearth,” the authors write, concluding that married women are prioritizing housework over leisure time or sleep as they conform to societal expectations around gender.
It’s not that having another adult in the house always increases the household work to be done, a category including cleaning, doing dishes, grocery shopping, and more. Women with extended family around besides their husbands report spending less time on housework. “The research is really showing that men are not necessarily contributing in ways that are bringing about equality in the home,” author Pepin of UT-Austin tells Fortune.
Pepin and her co-authors started this research aiming to evaluate the “time poverty” thesis, which posits that single moms experience a disadvantage in their available time compared to married women. Their findings, gathered from the American Time Use Survey from 2003 to 2012 and limited to heterosexual partnerships, pointed to a different conclusion—that married women end up with extra work at home that single moms don’t do.
The authors’ findings are consistent with other research that has found that any gaps being closed between men and women’s labor at home are due to women abandoning some chores—not men picking up the slack.
The study didn’t find a significant difference in the amount of time married women compared to unmarried women spent on childcare, suggesting that women in all categories of partnerships prioritized caring for their kids.
“Our findings suggest that it is not just an additional pair of hands that is important,” the authors write, “To whom those hands belong also matters.”