Couples who share chores have more sex

Time has an article by Belinda Luscombe about sex among couples:

In the sixteen-round-boxing match that is figuring out how to apportion the domestic chores between husband and wife, dividing it up along gender lines is about to take a really painful punch to the face.
A study to be published in the Journal of Marriage and Family in August of 2016 has found that, among couples who share their chores more evenly, there is more sexual gratification. In fact, say the researchers, the only couples reporting having more sex than their forebears did are those who are both getting busy with the household duties.
This is significant, because as recently as 2013, there was a widespread belief that, when men and women strayed into each other’s domestic territory, they didn’t find each other as desirable. The thinking was that guys who did the washing up and women who changed the oil on the family car were somehow muting their masculinity or femininity and thus sending less robust come-hither sexual signals.
The new study, out of Cornell University, says the old data, which prompted a New York Times magazine cover story and such headlines as Difference Equals Desire was old and that newer statistics report the opposite effect. “The association between a non-traditional division of labor at home and couples’ sexual satisfaction and frequency has changed dramatically over the past two decades,” writes the study’s lead author, Sharon Sassler, a professor of policy analysis and management, in a briefing paper for the Council on Contemporary Families. “By 2006, couples who reported sharing housework fairly equally, with the man doing more than a third and up to sixty-five percent of the housework, reported having sex significantly more often than did couples where the woman (or the man) did sixty-five percent or more of the housework.”
Why do chores change anything? “The evidence shows that when men do a greater share of housework, women’s perceptions of relationship fairness and satisfaction are greater,” writes Sassler. And when couples are more satisfied with their relationships, they tend to get it on more often. The secret ingredient, especially, seems to be childcare.
Historian Stephanie Coontz notes that this is in keeping with recent scholarship, that suggests that marriage is changing from a union in which two opposites worked together to make up for each other’s deficits, into a union based on shared interests, activities and emotions, the ramifications of which are explored in a recent Time cover story. “Where difference was once the basis of desire,” says Coontz, “equality is increasingly becoming erotic.”
It should also be noted that frequency and satisfaction are not always the same thing. “In marriages of the 1950s and 1960s, wives often reported having sex more often than they wanted because they were dependent on their husbands,” notes Coontz. “Now that women feel free to say no, they are more likely to say yes when they feel the relationship is fair.”

Rico says that sometimes, after menopause, they don't...