From today's NY TImes:
While married mothers and married fathers were approaching “gender equality,” measured by total hours of work, the researchers found stark differences among women. These disparities suggest why working mothers often feel hurried and harried.
Over all, the researchers said, employed mothers have less free time and “far greater total workloads than stay-at-home mothers.” The workweek for an employed mother averages 71 hours, almost equally divided between paid and unpaid work, compared with a workweek averaging 52 hours for mothers who are not employed outside the home.
On average, the researchers said, employed mothers get somewhat less sleep and watch less television than mothers who are not employed, and they also spend less time with their husbands.