WASHINGTON (AP) — Working mothers increasingly want full-time jobs, and tough economic times might be a big reason, according to a national survey.

In the Pew Research Center study being released Thursday, researchers saw a big spike in the share of working mothers who said they'd prefer to work full time; 37 percent said that was their ideal, up from 21 percent in 2007.

The poll comes amid a national debate on women in the workplace ignited by top Facebook executive Sheryl Sandberg, who writes in a new book about the need for women to be more professionally aggressive.