Philipps began her late-night show "Busy Tonight" on Tuesday by bringing up Georgia's bill, described as one of the most restrictive in the nation, outlawing an abortion once a fetal heartbeat is detected. That can come as early as six weeks, before many women are aware they are pregnant.
Speaking to reporters earlier in the day, Gov. Brian Kemp had said the bill ensures that "all Georgians have the opportunity to live, grow, learn and prosper in our great state."
"Women and their doctors are in the best position to make informed decisions about what is best for them. Nobody else," she said, going on to cite research showing that nearly one in four women will have an abortion by their 45th birthday.
"That statistic sometimes surprises people, and maybe you're sitting there thinking, 'I don't know a woman who would have an abortion.' Well, you know me," she said.
"I had an abortion when I was 15 years old. I'm telling you this because I'm genuinely really scared for women and girls all over this country," Philipps said, her voice breaking. "I think that we all need to be talking more and sharing our stories more."
Philipps then deadpanned a transition to a segment about fashion at the Met Gala but quickly circled back: "Is [that transition] kind of jarring? Yes, it is kind of jarring. But guess what -- that's what being a...woman is. Having a regular Tuesday and then suddenly being reminded that people are trying to police your body and then you just have to go back to work."
Philipps later tweeted that she spoke out "because I cannot sit idly by while women's rights are stripped away."
In the first few months of 2019, similar "heartbeat" abortion bans have been signed into law in Mississippi, Kentucky, Ohio and now Georgia.
Lawmakers in other states including Tennessee, Missouri, South Carolina, Florida, Texas, Louisiana and West Virginia, are considering proposals similar to Georgia's. A bill that recently passed the Alabama House would outlaw abortions at any stage of pregnancy, with a few narrow exceptions.
Kentucky's law was immediately challenged by the ACLU after it was signed in March, and a federal judge temporarily blocked it. Earlier versions of the law passed in North Dakota and Iowa have also been struck down in court.
The Associated Press contributed to this report.