The ad, directed by Rob Reiner and his wife, Michele, features the actresses speaking to the camera about Romney's statements that he would end funding for Planned Parenthood and appoint Supreme Court justices that would overturn Roe v. Wade.
Johansson also references an attempt by some House Republicans to redefine the rape exception in legislation providing federal funding for abortion, while Longoria speaks against a bill in the Virginia state legislature that would have required, in some instances, invasive ultrasounds for women seeking abortions.
“Mitt Romney wants to take away women’s control of their own bodies,” said MoveOn.org creative director Laura Dawn, in a statement announcing the new ad. “MoveOn is releasing this ad to help ensure that women voters know just how backward and extreme Mitt Romney is when it comes to issues affecting women.”
MoveOn said Monday the ad was a "six figure buy" and would air in Colorado and Virginia.
The new ad comes as President Obama and liberal allies have more aggressively hit Romney on women's issues in recent days, after polls showed the GOP nominee posting sizable gains among female voters in polling after the first presidential debate.
On Friday, the Obama campaign released an ad criticizing Romney for past statements he made saying he would cut federal funding for Planned Parenthood.
Abortion-rights advocates have also seized on a recent Romney remark suggesting that he would not push measures to restrict abortion rights if elected.
Last week, Romney told the Des Moines Register in an interview that there was "no legislation with regards to abortion that I'm familiar with that would become part of my agenda.”
The Romney campaign later clarified that he was "proudly pro-life and will be a pro-life president." But abortion-rights advocates said that Romney was trying to downplay his views on women's issues to target female swing voters.
This post was updated at 1:18 p.m.