The Life Of Cait star also recalled that she once considered suicide before undergoing gender reassignment surgery.
"Piers told her: "[Kris] has inferred pretty strongly that you mislead her, that you weren't honest with her when you got married because you had already attempted to transition once and then stopped, is it true that you were not honest with her?"
Additionally, the 68-year-old does not believe the family is "entitled to know before the world" as the surgery was "not that big a deal". It's a very serious part of my life.
Piers went on to press on whether "life could be funny", but she continued: "I take that very seriously and so out of respect to myself and the community, it's not something that you joke about".
The ITV special is due to air tomorrow, however audiences have been treated to a quick snippet - and Ms Jenner does not hold back.
During the interview, Caitlyn was shocked when Morgan pulled out an old doll of Bruce, which was released in the wake of his 1976 decathlon victory at the Montreal Olympic Games, to ask her about her gender transition surgery. People die over these issues.
Caitlyn told him: "You made a comment there and that's why you would get in trouble, OK?"
"I had been on hormones for four and a half years.there are changes when you are on hormones which are tough to hide". "I spent 23 years carting them around". I called Kendall the next day and said, "You know what it was a good ice breaker".
Caitlyn has two children Kendall and Kylie with momager Kris Jenner.
During her marriage to Kris Jenner, Caitlyn reportedly shied away from her biological children from previous marriages, which includes Brody Jenner, 34, and Brandon 36, from marriage to Linda Thompson and Burt, 39 and Cassandra, 37, from her marriage to Chrystie Jenner, in order to raise the Kardashian children as her own. "I want my voice to be heard and I want to see if I can make a difference". "I don't talk to the Kardashians anymore", Caitlyn admits.
Ending the interview, Piers said he had learnt a lot, adding: "The one thing I would say in conclusion is Bruce Jenner was a hell of a guy, and Caitlyn Jenner you're a hell of a woman!"