Britney Spears says she had an abortion after getting pregnant with Justin Timberlake in the early 2000s.

People confirms that Spears' upcoming memoir, The Woman in Me, contains an excerpt about getting pregnant with Timberlake when the two pop stars dated in the early 2000s.

"It was a surprise, but for me, it wasn’t a tragedy. I loved Justin so much. I always expected us to have a family together one day. This would just be much earlier than I’d anticipated," Spears reportedly writes in the book.

Spears alleges Timberlake wasn't happy about the pregnancy, as he wasn't ready to have a child just yet.

"But Justin definitely wasn’t happy about the pregnancy. He said we weren’t ready to have a baby in our lives, that we were way too young," Spears writes, according to People.

The pair would have been about 19 years old at the time.

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"I don’t know if that was the right decision. If it had been left up to me alone, I never would have done it. And yet Justin was so sure that he didn’t want to be a father," the excerpt continues, with Spears calling the abortion "one of the most agonizing things I have ever experienced in my life."

Timberlake has not responded to Spears' claim as of publishing.

Spears and Timberlake first met on the set of The All-New Mickey Mouse Club in the early '90s.

The former couple dated from 1999 to 2002. After breaking up, the pop stars allegedly wrote songs about each other, with Timberlake's "Cry Me a River" supposedly about Spears and Spears' "Everytime" allegedly about Timberlake.

The Woman in Me is out Oct. 24.

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