The New York Times shows the correlation between working mothers and satisfaction (including a chart of survey findings).
Andrew J. Cherlin and Prem Krishnamurthy write (excerpt):
. . . Working mothers clearly protect their family time: even as their free time falls by 32 percent, time with their children drops by only 16 percent.
This leisure gap takes its toll on working mothers, although they compensate by doing less housework. Twice as many employed mothers as non-employed mothers say that they “always feel rushed.” Yet the percentage saying they got a “great deal” or “a very great deal” of satisfaction from their family lives is somewhat higher for mothers who work than for those who don’t; perhaps a busy life that combines employment and child rearing is also a fulfilling one.