Caitlyn Jenner completes her transition

Caitlyn revealed that she had gender reassignment surgery in January this year and she uses her memoir to open up about her decision to go through with the procedure.,

The Keeping Up With the Kardashians star says that the surgery was costly, but that she is pleased with the results. 

"You want to know, so now you know. Which is why this is the first time, and the last time, I will ever speak of it," she writes in the book. 

ALSO READ: Kendall Jenner's Pepsi ad sparks backlash

According to reports, her memoir is set to reveal the reasons why she kept the truth about her sexual identity hidden for decades.

Radar Online reports that Caitlyn also makes a shocking revelation about OJ Simpson's murder trial in the memoire that will be released on the 25th of April."

"She says Robert Kardashian, who represented the NFL player, knew he was guilty of killing Nicole Brown Simpson and her friend Ronald Goldman," the online publication states.