After meeting on the set of "The Mickey Mouse Club" as kids, Spears and Timberlake began dating in 1999, though they didn't go public with their romance until a year later. The two eventually parted ways in 2002 following rumours that Spears cheated on him with choreographer and frequent collaborator Wade Robson.
According to People, Spears reveals in her upcoming memoir, "The Woman in Me," that she got pregnant with Timberlake's baby when they dated and had an abortion.
"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 writes of the pregnancy in the book, per the publication. "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."
Timberlake's rep did not immediately respond to POPSUGAR's request for comment.