(KTLA) – Britney Spears and Justin Timberlake were considered pop culture’s royal couple in the late ’90s and early 2000s.

In her upcoming memoir “The Woman in Me,” Spears revealed the couple became pregnant and ultimately decided to have an abortion.

In an excerpt obtained exclusively by People, Spears opened up about the painful secret she had been keeping for over 20 years.

“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,” she wrote. “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.”

The former “Mickey Mouse Club” members dated from about 1999 to 2002. TMZ estimates the two were around 19 years old at the time Spears is describing.

“I’m sure people will hate me for this, but I agreed not to have the baby. 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,” she said.

Spears further described the whole experience as “agonizing.”

Sources for the New York Post’s Page Six had previously claimed Timberlake was concerned about Spears’ forthcoming book.

“It’s eating at him,” one source told the outlet.

As of Wednesday morning, Timberlake had not publicly commented on Spears’ book or the excerpt published in People. Nexstar’s KTLA has reached out to Timberlake’s team for a comment.

Spears went on to have two sons, Sean Preston and Jayden James, with ex-husband Kevin Federline.

Timberlake went on to marry actress Jessica Biel. The pair have two sons together.

“The Woman in Me” will be released Oct. 24.