Researchers at George Mason and North Carolina State reported that women who are married do more housework than those who are part of a cohabitating couple (See, here and here.) The researchers theorised that
The average age was 44 among the 9,517 women surveyed; it was 48 for the 8,119 men. The survey found about 14% of the men and the women were cohabiting with an unmarried partner, and the rest were married. About 40% of the women were employed full time, as were about 66% of the men. Davis says no information was collected about the length of marriages or cohabiting relationships.
So men work longer hours than women. Presumably, married couples are more likely to have children; the woman would work part-time or stay at home, and, presumably, would take on more household work in exchange for not having a career. While the out-of-wedlock birth rate has increased in recent years, more children are born to married parents than to single mothers: 37% of children are born out-of-wedlock, while 63% are born to married parents (See, here). The researchers controlled for employment status; however, married men tend to work longer hours than cohabitating men. Married couples may be more likely to share a house than an apartment; yard work and maintenance may not be included in the definition of “household labour,” but would undoubtedly change the perception of the division of labour.
Ideally, the NC State and GMU researchers would have done a longitudinal study of couples who cohabitate and then marry, without changing residences or the number of children in the household. As such, they could determine if the actual marriage act, independent of other variables, affects the division of labour. The study, as it stands now, has variables that cannot be quantified, such as the nature of people who cohabitate instead of marry; the effects of marriage upon other, non-household tasks; and the effects of the type of residence upon the division of labour. So, ladies, calm down: men who walk down the aisle don’t stop caring about dust bunnies.