Elizabeth DeLong had hoped to take a year off after having her daughter, Grace, last August. But just a month later, Washington Mutual was seized by federal regulators, making her husband's position with the bank precarious.

The 29-year-old, who had arranged for a lengthy unpaid leave, realized she needed to return to work as quickly as possible, rather than spend time with her child. "I felt angry," she says.

As millions of Americans lose their jobs, others are reluctantly rejoining the work force: new mothers. Women who had hoped to take off a few months -- or, in some cases, a few years -- to raise their children are heading back to work sooner than they had expected.

Of course, for many working mothers, taking more than a few weeks or months off work after the birth of a child isn't an option. About 60% of women with children under the age of six are in the paid work force, according to U.S. government figures.

But evidence is mounting that more are joining their ranks. Mom Corps, a staffing company geared toward mothers looking for flexible work arrangements, has noticed an increase in the number of hours its members are looking to work. In the past, a typical work arrangement was between 20 and 25 hours a week, says Mom Corps Chief Executive Allison O'Kelly. Now, most applicants are looking to work 30- to 40-hour weeks. And since last year, traffic on the company's Web site has increased 79%, and the company's résumé-writing service is twice as busy, says Ms. O'Kelly.

In a recent online poll of members of CafeMom.com, a social-networking site for mothers, 16% of 14,416 respondents said they are now finding work because of the economy.