Young working moms are looking to work even harder, according to a study by the nonprofit Families and Work Institute.

Researchers found that 69 percent of young working mothers say they want to move up on the career ladder, compared to 66 percent of women without children. Of the 3,500 wage, salaried, and self-employed workers and small business owners surveyed, two-thirds of both men and women under age 29 say they want more responsibility on the job. When the same survey was conducted in 2002, only 48 percent of young working mothers responded that they wanted more responsibility, compared with 66 percent of men and 61 percent of childless women.

Ellen Galinsky, president and co-founder of the Families and Work Institute says the study marks a turning point. "It revealed for the first time that younger women are equally as ambitious as men," she says.

Galinsky attributes the shift to new expectations for women, especially young mothers. "Their roles have changed from taking care of the family in the traditional way to taking care of the family economically," she says, "Women have become more important financial providers."

Companies will need to adjust to keep up with changing ambitions, but not all employers are ready just yet, Galinsky says. "I don't think we have fully moved to a place where people are thinking about flexible careers," she says, "While some companies are, we still have a model that assumes that workers have someone else at the home to provide support."