In an interview with Elle magazine, she opened up about why the group is important to her.
"It's always been around for me, as far as I can remember. There wasn't a time that there wasn't a Planned Parenthood [available to me]," she said. "And I'm fortunate. I've always had medical care. I've always had access. I've never personally had to use a Planned Parenthood. But I have many friends who have and do and did, and I think it's important that that access be there for everyone."
Rhimes added that Planned Parenthood isn't just a "women's issue."
"The fact that I've never had to use a Planned Parenthood, the fact that I've never been in need of medical services I couldn't afford or didn't have access to, doesn't mean I shouldn't be concerned about the fact that other women don't have that access," she said.
Rhimes also said she thinks it's "simplistic and silly" to think women's health doesn't concern men.
"Obviously, it concerns them," she said. "It should obviously concern them. When you help make people healthier, it makes the nation healthier, it makes the world healthier, it makes the economy healthier."
Fans of Rhimes' shows know that the producer and writer doesn't shy away from addressing women's health issues -- including abortion -- in her work, and she doesn't make any apologies for that.
"I wasn't sure what everyone was so concerned about," she said. "I was accurately portraying a medical procedure that the Supreme Court says people are allowed to have. I wasn't going to pull any punches."
As far as her new role with Planned Parenthood goes, Rhimes said she wants to help "in any way that I can." She already has experience volunteering and serving on the board of the Los Angeles chapter of the organization, so she's ready to get to work.
"I think it's important for women to have a means to get health care. I think it's important that women have a place to go to get pap smears and cancer screenings. And it shouldn't be considered extra," she said. "It shouldn't be considered something that can get 'cut.' It shouldn't be something that's in danger of going away. The idea that we're even thinking about cutting that off because somebody else isn't enjoying it themselves or somebody has extreme opinions about it is worrisome to me."