According to researchers who observed 30 dual-earner couples in Los Angeles with at least one child aged 8-10, women are screwed.
Or, to be more precise, the researchers looked at levels of the stress hormone cortisol in the couples, which had the median age of 41, and how those levels declined at the end of the day with the post-work, pre-sleep wind-down. According to the LA Times,
Lots of time spent in household chores at the end of the day keep both husbands' and wives' cortisol levels high—no surprise here. But on closer inspection, the researchers observed that a married mother's cortisol levels will decline most steeply at the end of the day when her husband pitches in with the housework. Unfortunately, a working man's end-of-day cortisol levels won't likely dip to recovery levels unless he spends more of his end-of-the-day time relaxing and his female partner spends less time relaxing.
At first, we thought this reliance on the female partner relaxing less was not so much because the "working man" is a jerk and more because someone has to do the housework and most often that someone is a woman. But then we read some more and realized that it's exactly the way it sounds: "Your biological adaptation to stress looks healthier when your partner has to suffer the consequences – more housework for husbands, less leisure for wives," said the lead researcher. Specifically, men were less stressed when their wives were doing housework.
And indeed, in these couples, that's exactly what happened: When the researchers monitored the homes of the couples, the women spent 30 percent of their after-work time doing housework, 18.5 percent "in communication," and had about 10 percent devoted to leisure time. Men spent around the same time communicating, but since they spent only 20 percent of their time doing housework, they had about 19 percent of their time to spend on leisure. (Maybe they were watching tentpole movies? Or Two And A Half Men?)