In a harrowing new ad made by MoveOn.org, 'House' star Lisa Edelstein takes on Republican legislation that would severely reduce women's reproductive rights.

As she walks down a long hallway dressed in 50s garb, Edelstein narrates the ad:

"Decades ago, women suffered through horrifying back alley abortions. Or, they used dangerous methods when they had no other recourse. So when the Republican Party launched an all out assault on women's health, pushing bills to limit access to vital services, why is the GOP trying to send women back ... to the back alley?"

The ad closes with a shot of Edelstein dressed in modern clothes, desperately reaching for a coat hanger in the closet.

Nancy Pelosi has also spoken out against the proposed pieces of legislation, which would punish employers for providing insurance that includes abortion access, allow hospitals to turn away women who need abortions to save their own lives and end Title X, a federal grant program that supports family-planning organizations like Planned Parenthood.

"They're advancing extreme legislation," Pelosi said. "It's dangerous to women's health, disrespects the judgment of American women -- I don't know if they even gave that a thought -- and it's the most comprehensive and radical assault on women's health in our lifetime. It's that bad."

On Tuesday, lawmakers in South Dakota moved to expand the definition of "justifiable homicide" to include the killing of people who intend to harm a fetus.

Meanwhile, Justin Bieber has come out against "killing a baby," even in cases of rape.

"Um. Well, I think that's really sad, but everything happens for a reason," he said. "I guess I haven't been in that position, so I wouldn't be able to judge that."

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