I'm curious - is your personal evidence anecdotal, qualitative, quantitative...?

Michael Vassar also makes a good point - the values and implications of "traditional roles" vary a great deal across time, and especially across socioeconomic status. There are certainly career women in the West who perceive taking time off to care for children as a relief from the rat race and a chance to contribute to society in another positive way. They might feel differently had they been, say, a 12-year old Zimbabwean girl who never attended school, was married to an older man to help her family's finances, developed an obstetric fistula in childbirth, and never left her husband's compound again. That isn't just traditional, it's an active reality for millions of poor women around the world. There are also many happy, healthy, educated African career women and stay-at-home-moms, of course. The context of "tradition" is very important.