Aug. 22, 2010— -- Supreme Court Justice Sonia Sotomayor, Homeland Security Secretary Janet Napolitano and former Secretary of State Condoleezza Rice -- what do these women have in common?
Despite their widely varying political and personal experiences, all three of these powerful women do not have children, and some experts think this fact may have contributed directly to their successes.
A new study from the University of Chicago claims that childless women become more successful in the workplace than women with children.
Men and women have nearly identical incomes and working hours once graduating from college, but 15 years later the men's incomes soar to 75 percent more than incomes earned by women, according to the study.
The only exception to the rule is the small group of women who have never had children and whose pay equals that of their male peers.
Kiki Peppard spent a decade working as a successful bookkeeper before taking leave to spend more time with her children. When she decided to re-enter the workforce following a divorce, she found herself as a mother on the outside of the professional world.
"The very first question I was asked was, are you married? The second was do you have children?" she told "Good Morning America." "I went on 18 interviews and was asked if I was married or had kids, on the 19th one I finally wasn't asked about my kids or husband and got the job."
It's often assumed that women make less than men because they have more career disruptions such as pregnancy and raising children, but the pay disparity between men and women also pits mothers against non-mothers.
Mothers are 44 percent less likely to be hired than women without children, and they are paid $11,000 less, according to a 2005 study from Cornell University.
That bias in this uncertain economy can be devastating to many families and can mean the difference between paying monthly bills on time and going further into debt.
An Outdated Work Policy Structure
"The maternal wall is standing in the way of the glass ceiling," said Kristin Rowe-Finkbeiner, Executive Director of MomsRising.org in an interview with "Good Morning America." "Women without children make 90 cents to a man's dollar, while women with children make only 73 cents to a man's dollar. We have a huge problem with pay discrimination against mothers."
Rowe-Finkbeiner points out that women are now more than 50% of the labor force for the first time in history, yet many mothers are working on a full-time basis and are still unable to put food on the table. One in four children in the U.S. is experiencing food scarcity because of economic limitations, according to the USDA.
Solutions to these problems exist, she says, such as passing family friendly policies, like paid family leave, affordable child care, access to paid sick days and access to flexible work options.
"Those things actually help lower the wage gap between women and men. And they raise all boats. It's not just moms that need those policies in order to excel in their life, in the workplace and with their families," she says.
Rowe-Finkbeiner goes on to explain that professional women who leave the workforce should take important steps that will ease the process of reentering it. First, maintaining one's professional contacts and accreditations will ideally lead to smooth sailing when returning to the workforce.
Another helpful tactic is finding a mentor -- a professional who has navigated these seas before, and who can help with the transition back into the workplace when the time comes.
Finally, finding volunteer positions to add to a resume will show to employers that -- in addition to the difficult job of raising children --the working mother was productive.
Though this will help with the transition for working mothers, the U.S. lags behind most countries that have modernized their policies -- a whopping 177 other countries have adopted paid family leave.