Why married mothers end up doing more housework when they start out-earning their husbands

The idea of a male "breadwinner" in married heterosexual couples might seem old fashioned. But as a social construct, the view that a husband's primary role is to earn money has proved to be exceptionally durable.

Research shows that in many countries there is still a strong expectation that men will be the main income provider in the family—and that perceptions of masculinity are linked to this being the case.

So what happens when a woman earns more money than her husband? Studies indicate that couples which move away from the traditional role of a male breadwinner may be seen (by themselves and others) as deviating from the norm. And as this has become more common over recent decades, a theory has emerged that these couples seek to adjust their domestic roles to compensate.

Known as "gender deviance neutralization", it suggests that when the man earns less than the woman, couples respond to their "non-traditional" income arrangement by becoming decidedly more traditional about who does what in terms of housework. Put simply, higher earning wives end up doing more of the chores.

This is the opposite of what rational economic theories predict, that the partner with lower earning potential will focus more on domestic chores to maximize the overall household standard of living.

So we have two established—and competing—ideas about what happens when wives earn more than their husbands. This is further complicated by a lack of empirical consensus when these theories have been tested using household data on income and time use.

But my research now reveals a key factor when it comes to which theory better applies to housework division and the effect of different earning levels within a couple. And that factor is parenthood.

As most parents will recognize, the birth of a child increases both the domestic workload and the pressure on household income. Babies bring joy, but also a considerable amount of work and expense.

And surprisingly, it is the first of the theories (as wives earn more they also start doing more of the housework) which better describes the time spent on housework—excluding childcare—when a couple become parents.

Domestic bliss

Children have a significant impact on how their parents deal with time, money and chores. According to one study, the most common area of contention among couples with children is precisely the division of domestic duties and responsibilities. It goes on to suggest that this is primarily due to the clash between the traditional division of labor along gender lines and the modern reality of working mothers often earning more than their male partners do.

But while parenthood could theoretically lead to a more efficient division of labor, in my research I found it crystallized that traditional gendered separation.

Using data gathered over 18 years from over 6,000 dual-income heterosexual couples in the US by the Panel Study of Income Dynamics, I examined the impact of having children on the relationship between how much time both partners spent on housework, and the difference in income between them.

When it came to domestic arrangements, parents showed a marked tendency towards gender deviance neutralization. For childless couples, the division of housework wasn't related to how much each partner earned.

In fact, these effects are so sizeable that as a mother's relative income increases, so too does her share of the housework.

The striking result of this study was that the woman taking on more of the housework happens not when wives out-earn husbands, but when mothers out-earn fathers. This is not necessarily an intuitive result, as you might expect that the increased financial and domestic demands that come with having children would lead to an efficient, and not necessarily gendered, division. Specifically, for a wife who earns more than her husband, taking on more domestic duties as well after becoming a mother may not maximize the household's quality of life.

How couples divide the increased domestic workload after becoming parents is an important factor in the earning inequality between women and men over their lifetimes. A pattern once settled upon is often difficult to renegotiate, and even wives who initially earn more than their husbands could see a long-term reduction in their future earnings potential.

And through passing on norms and beliefs to the next generation, these couples' children may well repeat them as adults. One expectation of the "gender revolution" of the 1960s and 70s was that women's increased presence in the workplace and earning potential would be accompanied by men's greater participation in domestic activities. But my research suggests that many parents still have a long way to go.