Heigl announced on the Ellen DeGeneres show, in an episode scheduled to air tomorrow, that she and husband musician Josh Kelley are adopting a special needs child from Korea.
"It is a little girl, and she'll be 10 months at the end this month," Heigl told DeGeneres, according to People magazine. "She was actually born the day before me in November, which I thought was really serendipitous and just kind of like a sign. I realized just recently that I basically forfeited my birthday for the rest of my life."
Heigl's sister Meg was also was adopted from Korea, according to People.
"Her name is Naleigh," Heigl said. "I am naming her after my mother and sister Nancy, Leigh. So we call her Naleigh."
She said her new daughter will be coming "real soon."
"I wanted to tell everybody so you don't think I stole a Korean baby," she said, laughing.
RadarOnline, which first broke the news of Heigl's impending adoption, said it had been in the works for about six months. Heigl and Kelley were married in December 2007.
But the idea of adopting was planted long ago. The "Grey's Anatomy" star told USA Today two years ago that it was "always planned."
"I'm done with the whole idea of having my own children," Heigl told the newspaper.
Heigl joins other well-known celebrities who have adopted transracially and overseas.
Recently, Madonna fought the Malawai government and won the right to adopt 4-year-old Mercy. Two years earlier, she adopted a boy from Malawai, David Banda, now 3, with ex-husband Guy Richie.
But Madonna was widely criticized the second time around for adopting overseas when there are an estimated half-million children in foster care in the United States.
Not everyone's a critic, however.
Adoption advocates say that the need to place children in good homes knows no borders.
"I think that this construct of one child versus another is really unhealthy," Adam Pertman, executive director of the Evan B. Donaldson Adoption Institute, a research and advocacy group, told ABCNews.com. "They both need homes. How can we put one kid against another?"
"On the positive side -- and I think it's mainly positive -- maybe they can help normalize this process," Pertman said about transracial adoptions. "If Angelina Jolie and Steven Spielberg and Hugh Jackman did it, it must be OK. And that normalization is good for kids."
"The big negative is this notion of adoption as baby buying and something only people of privilege get to do, that Madonna stepped to the front of the line, and how is Angelina going to raise all these children," he said. "It's this notion of children as trophies. And it's just not true. There is no evidence she's doing anything illegal or unethical. She's simply getting more attention."
But the attention that's paid to celebrities who adopt transracially diverts attention from the real story facing African-American children and adoption, experts say. There was a small increase in transracial adoptions from 17.2 percent in 1996 to 20.1 percent in 2003, according to a study by the Donaldson Institute.