Britney Spears is sharing all her secrets in her upcoming memoir, "The Woman in Me."

In the book, set to release later this month, the 41-year-old pop star opens up about drug use, cheating, an abortion and the reason she shaved her head.

Excerpts shared by People and The New York Times cover several areas of Spears' life, from her child star days on Disney's "The All New Mickey Mouse Club" through the dissolution of her controversial conservatorship.

BRITNEY SPEARS SAYS SHE HAD ABORTION WITH JUSTIN TIMBERLAKE IN BOMBSHELL MEMOIR

Britney Spears then and now split

Britney Spears gets personal in her upcoming memoir. (Getty Images)

Mickey Mouse Club 

Spears had brushes with fame early in her life, including a notable turn on "Star Search" when she was 10, but her first big break came when she was cast on the "Mickey Mouse Club" revival on the Disney Channel in 1992.

In the book, she discussed being a Mouseketeer on the show from 1989 to 1995. She appeared alongside stars like Christina Aguilera, Ryan Gosling and fellow pop star and former flame Justin Timberlake.

A photo of Justin Timberlake and Britney Spears

Justin Timberlake and Britney Spears dated from 1999 to 2002. In the book, Spears discussed being a Mouseketeer on the show from 1989 to 1995. She appeared alongside stars like Christina Aguilera, Ryan Gosling and fellow pop star and flame Justin Timberlake. (Dave Hogan)

"Being in the show was boot camp for the entertainment industry: extensive dance rehearsals, singing lessons, acting classes, time in the recording studio, and school in between," she recalled. "The Mouseketeers quickly split into our own cliques, divided by the dressing rooms that we shared: Christina Aguilera and I were the younger kids, and we shared a dressing room. We looked up to the older kids — Keri Russell, Ryan Gosling, and Tony Lucca, who I thought was so handsome. And I quickly connected with a boy named Justin Timberlake."

She called the gig "a kid's dream" and "unbelievably fun," but noted that "it was also exceptionally hard work: we would run choreography thirty times in a day, trying to get every step perfect."

Britney Spears and Justin Timberlake wearing denim outfits at the American Music Awards

It wasn't all work with the child stars though. Spears also mentions a game of truth or dare when someone dared Timberlake to kiss her.  (Jeffrey Mayer/WireImage)

It wasn't all work with the child stars though. Spears also mentioned a game of truth or dare when someone dared Timberlake to kiss her. She remembered a Janet Jackson song playing in the room as he followed through on the dare.

BRITNEY SPEARS BASHES POLICE FOR CONDUCTING WELFARE CHECK AFTER VIRAL KNIVES VIDEO: ‘ABOUT POWER FOR COPS’

Teenage 'daiquiri' drinking with mom

"The All New Mickey Mouse Club" was filmed in a studio in Orlando, Florida, and when the show was over, Spears made the decision to return to her hometown of Kentwood, Louisiana.

"Already within me was a push-pull: part of me wanted to keep building toward the dream; the other part wanted me to live a normal life in Louisiana," she wrote. "For a minute, I had to let normalcy win."

A photo of Britney Spears

"The All New Mickey Mouse Club" was filmed in a studio in Orlando, Florida, and when the show was over, Spears made the decision to return to her hometown of Kentwood, La. (George De Sota/Redferns)

For a while, she was able to lead a "normal teenage life." Part of this, she recalled, included traveling to Biloxi, Mississippi, with her mother and drinking daiquiris when she was in eighth grade.

"I loved that I was able to drink with my mom every now and the," she shared. "The way we drank was nothing like how my father did it. When he drank, he grew more depressed and shut down. We became happier, more alive and adventurous."

LIKE WHAT YOU’RE READING? CLICK HERE FOR MORE ENTERTAINMENT NEWS

A photo of Britney Spears

Spears revealed she and her mother drank together when she was a teenager. (Fryderyk Gabowicz/picture alliance)

She remembered this "beautifully normal" period of her life fondly but admitted she "missed performing." A lawyer that she and her mother knew, a man named Larry, suggested she record a demo. He was even able to supply a song for her, a track that had been cut from a Toni Braxton record.

"Larry took me around [New York City]," she wrote, "and I went into rooms full of executives and sang Whitney Houston’s ‘I Have Nothing.’ Gazing out at the rooms full of men in suits looking me up and down in my small dress and high heels, I sang loud."

After signing a record deal at 15, she threw herself firmly into recording.

Britney Spears behind a yellow backdrop

Spears signed a record deal at 15, and she threw herself firmly into recording. Britney Spears used a cut Toni Braxton song for her demo. (Kevin Mazur Archive/WireImage)

"I worked for hours straight," she wrote. "My work ethic was strong. If you knew me then, you wouldn’t hear from me for days. I would stay in the studio as long as I could. If anyone wanted to leave, I’d say, 'I wasn’t perfect.'"

Hollywood ‘occupational hazard’

Britney Spears, Zoe Saldana and Taryn manning filming Crossroads

By the time she was 20, Spears had already released three successful albums, and she'd filmed her first movie, "Crossroads." (Paramount)

By the time she was 20, Spears had already released three successful albums, and she'd filmed her first movie, "Crossroads." Released in 2002, it became an instant classic for many fans, but she had some difficult feelings attached to it.

"The experience wasn’t easy for me," she wrote of the filming process. "My problem wasn’t with anyone involved in the production but with what acting did to my mind. I think I started Method acting — only I didn’t know how to break out of my character. I really became this other person. Some people do Method acting, but they’re usually aware of the fact that they’re doing it. But I didn’t have any separation at all.

BRITNEY SPEARS ADMITS SHE FINDS SOCIAL MEDIA ‘ADDICTING,’ USES FILTERS ON HER PHOTOS

"I ended up walking differently, carrying myself differently, talking differently. I was someone else for months while I filmed ‘Crossroads.’ Still to this day, I bet the girls I shot that movie with think, She’s a little…quirky. If they thought that, they were right," she speculated of co-stars Zoe Saldana and Taryn Manning.

She called the movie "pretty much the beginning and end of my acting career," something that made her feel "relieved." Spears later appeared in single episodes of shows like "How I Met Your Mother" and "Will and Grace," but nothing nearly as involved as starring in her own movie.

A photo of Justin Timberlake and Britney Spears

Justin Timberlake attended the "Crossroads" premiere with Britney Spears in 2002. (Ron Galella, Ltd./Ron Galella Collection)

She did note that she almost got another opportunity to take a crack at Hollywood. She came close to getting the lead role in 2004's "The Notebook" that went to Rachel McAdams.

In the excerpts shared by People, Spears noted that "even though it would have been fun to reconnect with Ryan Gosling after our time on the ‘Mickey Mouse Club,’ I’m glad I didn’t do it. If I had, instead of working on my album 'In the Zone' I’d have been acting like a 1940s heiress day and night."

On acting, she wrote, "I hope I never get close to that occupational hazard again. Living that way, being half yourself and half a fictional character, is messed up. After a while you don’t know what’s real anymore."

Justin Timberlake

A photo of Britney Spears and Justin Timberlake

While she was becoming a pop icon, Spears was also busy in her personal life. In 1999, she reunited with Timberlake, and the two began a relationship that would last until 2002. (Kevin Winter)

While she was becoming a pop icon, Spears was also busy in her personal life. In 1999, she reunited with Timberlake, and the two began a relationship that lasted until 2002.

While they were together, fans gushed over their love story, but behind the scenes, things may not have been as cute as they appeared.

BRITNEY SPEARS ADMITS SHE ‘COULDN’T TAKE THE PAIN ANYMORE' IN FIRST STATEMENT ON SAM ASGHARI DIVORCE

Spears claims in her book she became pregnant at one point during their relationship, and the pregnancy ended with an abortion that she alleged was at Timberlake's insistence.

"It was a surprise, but for me, it wasn’t a tragedy," Spears wrote about conceiving. "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.

A photo of Justin Timberlake and Britney Spears

Britney Spears said she was "comatose" after Timberlake broke up with her. (Kevin Mazur Archive 1/WireImage)

"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.

"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.

"To this day, it’s one of the most agonizing things I have ever experienced in my life."

Reps for Justin Timberlake did not respond to Fox News Digital's requests for comment.

A photo of Justin Timberlake and Britney Spears

Britney Spears claimed she had an abortion after becoming pregnant with Justin Timberlake's baby (Scott Gries/NBAE/ImageDirect)

Elsewhere in the book, in quotes shared by the New York Times, Spears wrote about infidelity within the relationship. She claimed Justin had cheated on her, and she kissed choreographer Wade Robson in retaliation.

When Timberlake broke up with her, she said, he did it through a text. The singer wrote that she was "devastated" by the split and even considered leaving the music industry altogether.

She also discussed her reaction to "Cry Me a River," Timberlake's breakout solo song after he left boy band NSYNC. In the video, she described "a woman who looks like me cheats on him and he wanders around sad in the rain."

So many of his fans believed that she'd broken his heart, but Britney says she was "comatose in Louisiana, and he was happily running around Hollywood."

Partying and her shaved head explained

A photo of Britney Spears, Sean Combs, Paris Hilton, Dallas Austin

Britney Spears, Sean "Diddy" Combs, Paris Hilton and Dallas Austin attend 50 Cent Hosts Party at The Hard Rock Sept. 8, 2007, in Las Vegas. (Johnny Nunez/WireImage)

In the excerpts shared by The New York Times, Spears describes some of the moments that led to her conservatorship, which began in 2008.

While the need to help control her erratic behavior was the reason given for the conservatorship, Spears says her partying during this time "was never as wild as the press made it out to be."

She said she didn't take hard drugs and she "never had a drinking problem," although she did note the prescription medication Adderall was her "drug of choice." She explained it "made me high, yes, but what I found far more appealing was that it gave me a few hours of feeling less depressed."

A photo of Britney Spears

While the need to help control her erratic behavior was the reason given for the conservatorship, Spears says her partying during this time "was never as wild as the press made it out to be." (Michael Kovac/Getty Images for EJAF)

It wasn't partying, she wrote, that caused her concerning behavior. Spears says that when she walked into a salon and buzzed her hair as paparazzi watched and when she went after photographers with an umbrella, she did it because she was "out of my mind with grief."

"I am willing to admit that in the throes of severe postpartum depression, abandonment by my husband, the torture of being separated from my two babies, the death of my adored aunt Sandra, and the constant drumbeat of pressure from paparazzi, I’d begin to think in some ways like a child," she wrote of this difficult time.

Britney Spears on the cover of the Daily News

Spears says when she walked into a salon and buzzed her hair as paparazzi looked on, it was because she was "out of my mind with grief." (NY Daily News via Getty Images)

"With my head shaved, everyone was scared of me, even my mom. Flailing those weeks without my children, I lost it, over and over again. I didn’t even really know how to take care of myself."

Britney Spears arriving to court

Britney Spears arrives for a child custody hearing at Los Angeles Superior Court Oct. 26, 2007, in Los Angeles. (Matthew Simmons/WireImage)

In November 2006, Spears filed for divorce from husband Kevin Federline, citing irreconcilable differences. Three months later, she buzzed off hair, and, days later, she entered rehab. Federline was eventually given custody of their two sons, Sean and Jayden.

Costly conservatorship

"I’d been eyeballed so much growing up. I’d been looked up and down, had people telling me what they thought of my body, since I was a teenager. Shaving my head and acting out were my ways of pushing back," she wrote in an excerpt shared with People.

"But under the conservatorship," she continued, "I was made to understand that those days were now over. I had to grow my hair out and get back into shape. I had to go to bed early and take whatever medication they told me to take.

Britney Spears on the red carpet

Britney Spears was released from the conservatorship in 2021. (Getty Images)

"If I thought getting criticized about my body in the press was bad, it hurt even more from my own father. He repeatedly told me I looked fat and that I was going to have to do something about it," she added.

CLICK HERE TO SIGN UP FOR THE ENTERTAINMENT NEWSLETTER

"Feeling like you’re never good enough is a soul-crushing state of being for a child. He’d drummed that message into me as a girl, and even after I’d accomplished so much, he was continuing to do that to me. I became a robot. But not just a robot — a sort of child-robot. I had been so infantilized that I was losing pieces of what made me feel like myself."

Spears' father, Jamie, acted as her conservator from the time it was put in place in 2008 until it was dissolved in 2021. It was originally put into place when Spears was apparently struggling with her mental health. But, over the years, the details of its inner workings were mostly kept secret.

Britney Spears at an event

Britney Spears' memoir, "The Woman in Me," will be released Oct. 24. (REUTERS/Mario Anzuoni/File Photo)

The singer wrote, "The conservatorship stripped me of my womanhood, made me into a child. I became more of an entity than a person onstage. I had always felt music in my bones and my blood; they stole that from me.

"I know I had been acting wild, but there was nothing I’d done that justified their treating me like I was a bank robber," an excerpt from The New York Times states. "Nothing that justified upending my entire life. … Too sick to choose my own boyfriend and yet somehow healthy enough to appear on sitcoms and morning shows, and to perform for thousands of people in a different part of the world every week."

Jamie Spears and his daughter Britney

Britney Spears and her father, Jamie Spears, left, have had a strained relationship for years. (AP Photo/File)

Of her father, she wrote, "I began to think that he saw me as put on the earth for no other reason than to help their cash flow." She also remembered an occasion on which he said, "I’m Britney Spears now."

CLICK HERE TO GET THE FOX NEWS APP

Now that she's in control of her life again, Spears admitted to still struggling with what happened during the conservatorship.

"Migraines are just one part of the physical and emotional damage I have now that I’m out of the conservatorship," she revealed. "I don’t think my family understands the real damage that they did."

A rep for Jamie Spears said the family will not be commenting when reached by Fox News Digital.