Caitlyn Jenner reveals in her upcoming memoir that she underwent gender reassignment surgery in January of this year, almost two years after she revealed her decision to transition.
That reveal was the result of Jenner, 67, being annoyed by fans who were constantly asking about her genitals and whether or not she had kept the parts she was biologically born with or had surgery, she writes in 'The Secrets of My Life'.
'The surgery was a success, and I feel not only wonderful but liberated,' writes Jenner in her book according to Radar Online.
She also explains her decision had much to do with the discomfort that came with tucking away her penis.
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Changes: Caitlyn Jenner writes in her new memoir that she underwent gender reassignment surgery in January of this year (Jenner left in November 2015, right at the 1976 Olympic games)
Big debut: A post-surgery Caitlyn hit the red carpet at Elton John's annual Oscar party with model Andreja Pejic in February (above) who has also undergone gender reassignment surgery
'So why even consider it? Because it’s just a penis. It has no special gifts or use for me other than what I have said before, the ability to take a whiz in the woods,' writes Jenner.
'I just want to have all the right parts. I am also tired of tucking the damn thing in all the time.'
Jenner also writes about how good she felt after the surgery.
'I am going to live authentically for the first time in my life,' she writes of her thoughts after undergoing the procedure.
Jenner's memoir hits bookshelves on April 25
'I am going to have an enthusiasm for life that I have not had in 39 years since the Olympics, almost two thirds of my life.'
Jenner also writes to those curious minds who stop to ask her about her genital situation: '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.'
News of Jenner's surgery will be perhaps the biggest surprise in her new memoir, which netted her a $4million advance and was written with the help of 'Friday Night Lights' author Buzz Bissinger.
It is due to hit bookshelves on April 25.
Male to female gender reassignment surgery is a far less costly and far more successful procedure than the female to male procedure.
In the surgery, the testicles and most of the penis are removed while the urethra is shortened.
The skin that had been surrounding the penis is then inverted and used to create a functioning vagina as well as a neoclitoris in some cases, which allows for sensation.
That is done by using a 'composite graft of the tip of the penile glans' according to NCBI.
The prostate meanwhile is not removed during the surgery, though it does shrink because of the hormones that are taken during the transition process.
There is then a long period of maintenance following the surgery, which requires between four and six weeks of recovery.
Patients spend at least three days in the hospital and two weeks doing no activity that is in any way strenuous.
The body initially treats the vaginoplasty like a wound, meaning that dilation must be performed by the patient so their vagina does not close up.
This is done in most cases with a dildo or dilator, and for the first three weeks must be done three to four times a day for 15 minutes each time.
Male to female gender reassignment surgery is a far less costly and far more successful procedure than the female to male procedure.
In the surgery, the testicles and most of the penis are removed while the urethra is shortened.
The skin of the penis is then inverted and used to create a vagina.
In some procedures a neoclitoris is also created with that skin from the tip of the penile glans which allows for sensation.
The prostate meanwhile is not removed during the surgery, though it does shrink because of the hormones that are taken during the transition process.
After the surgery, patients spent three days in the hospital and must not do any strenuous activities for two weeks.
Initial recovery time is between four and six weeks for most patients, and after 12 weeks the patient is fully recovered.
Dilation must be performed by the patient multiple times a day for at least 12 weeks after the surgery for 15 minutes at a time, and at least once a week after that for the rest of their life.
Some doctors recommend daily dilation for life with the largest dilator or dildo the patient can comfortably fit into their new vagina.
At 12 weeks, the patient can have sex again and in most cases those who have had the surgery report that they are able to experience orgasms.
The procedure can cost anywhere from $5,000 to $100,000, with the average US surgery cost $20,000.
Bleeding, swelling and vaginal discharge are among the common side effects after surgery.
Daily dilation ends after week 12 in some cases, but after that the new organ must be dilated at least once a week for the remained of the patient's life.
Other doctors recommend daily dilation for the rest of the patient's life, using the largest dilator they can comfortably fit in their vagina.
The procedure can cost anywhere from $5,000 to $100,000, which is one of the reasons many of the estimated 700,000 transgender persons living in the United States cannot afford the surgery.
The average cost is somewhere around $20,000 in the United States.
Studies have found few negative side effects and many psychological benefits for transgender patients after they have undergone the procedure.
The most common side effects are bleeding and swelling from the surgery as well as vaginal discharge.
This is one in a list of procedures Jenner has undergone during her transition, along with breast augmentation and facial feminization surgery.
The facial surgery Jenner had done, during which her brow was lifted and her jawbone shaved, cost approximately $70,000 and took 10 hours to complete.
Jenner also had a tracheal shave in late 2014, after which he was photographed by the paparazzi as he left the clinic.
Jenner publicly revealed she had transitioned in a 20/20 interview back in April of 2015 with Diane Sawyer, telling the veteran newscaster: 'For all intents and purposes, I am a woman.'
She went on to say in that interview: 'My brain is much more female than it is male. That's what my soul is. Bruce lives a lie. She is not a lie. I can't do it anymore.'
That June, Jenner appeared on the cover of 'Vanity Fair' wearing a white satin bustier with the words: 'I Am Caitlyn.'
She said in the accompanying interview that shooting the cover of the magazine was better than winning an Olympic gold medal.
'The last few days of doing this shoot was about my life and who I am as a person,' said Caitlyn.
'It's not about the fanfare, it's not about the people cheering in the stadium, its not about going down the street getting an ''Atta boy Bruce" pat on the back, okay, this is about your life.
'Soon as the Vanity Fair cover comes out, I'm free.'
Later that day Jenner created a Twitter account, writing in her first tweet; 'I’m so happy after such a long struggle to be living my true self. Welcome to the world Caitlyn. Can’t wait for you to get to know her/me.'
While she was away: Jenner kept a remarkably low profile around the time she underwent the procedure, and explained her absence on Instagram by saying that she had been busy singing books (above) from the New Year to Martin Luther King Day
Family matters: Jenner (above with daughters Kendall and Kylie on Thanksgiving) also underwent facial feminization surgery in 2015
Jenner has previously refused to answer questions about her genitalia in interviews - including Sports Illustrated in 2016
It was also announced in June of 2015 that Jenner would begin appearing in the E! reality show I Am Cait, which debuted one month later in July and was recently cancelled after two seasons.
And that busy summer was capped of with her official name and gender change in September.
Jenner has refused to comment on whether or not she underwent gender reassignment surgery multiple times in the past, most recently when appearing on the cover of 'Sports Illustrated' last June.
'It’s nobody’s business whether I want to do that to my body,' said Jenner, who posed on the cover with her Gold medal from the 1976 Games.
She also spoke in that interview about how the decathlon was a distraction at the time from her feelings that she was in fact a woman trapped inside the wrong body, and once again speaks about this in her interview.
'For those two days in July of 1976, I was the best in the world at what I did,' says Jenner.
'On the other hand, the decathlon was my best friend, and that was over. I lost my beard.'
At that point Jenner - who was 26 when she won her medal - said she had known for years that there was something female inside of her, she just did not know how to deal with it at the time.
She also makes a point of stating that she never once tried to suppress how she felt inside, but rather found something else to focus on to take her mind off of things.
'Little Caitlyn has been in there since I was this big,' says Jenner at one point in the interview, raising her hand just a few feet off the ground.
'Sometimes she raised her cute little head more than others. I was female inside, but I wasn’t an effeminate male. So I could hide easily in the male world.
'My life was distraction after distraction after distraction. Being a macho male was a way for me to try to convince myself that the woman living inside of me really isn’t living inside me.'
Getting started: The testicles and penis are removed during the early stages of male to female gender reassignment surgery (left before being cut, right after the testicles and penis have been removed)
Next up: The urethra is then shortened on the male while a 'composite graft of the tip of the penile glans' is used to make a neoclitoris
Finishing up: The procedure can cost anywhere from $5,000 to $100,000 (functioning vagina above)
Jenner said in the Sports Illustrated film Jenner: 40 Years After Gold: 'I had proved myself as a man. And I still had this person living inside me that I had never, ever really dealt with.'
Jenner joked about her life now at one point when pointing out the she has won an Olympic gold medal in the men's decathlon and a Glamour Woman of the Year award.
'This has got to be the greatest double of all time, right? It will never be matched,' says Jenner.
The interview also reminds readers just how impressive Jenner's record-breaking feat was at the 1976 Olympics, noting that her numbers who have qualified her for a spot on the current Olympic team, an unheard of feat in the sports world.
To get in that shape required years of hard work and training, and as a result gave Jenner the body of an Adonis, something she did not care for at all at the time.
'It disgusted me. I was big and thick and masculine. The rest of the world thought it was this Greek god kind of body. I hated it,' says Jenner.
'But it’s what I was given, so I just tried to do the best I could with it.'
This feeling of disgust Jenner had with her body is one of the reasons she began considering plastic surgery at such a young age she explains, wanting to have procedures done almost immediately after the Olympic Games.
'I was always considering plastic surgery,' says Jenner.
'When you’re gender dysphoric, you’re constantly looking at yourself and seeing things that don’t look right.'