Olympic gold medalist McKayla Maroney has revealed that she was sexually abused by the former USA gymnastics doctor for seven years.

Maroney, 21, said on Tuesday night that convicted sex offender Dr Larry Nassar molested her from the age of 13 until she left gymnastics last year.

The abuse happened at many high-profile competitions, including the 2012 London Olympic Games where she won gold and silver medals, Maroney said.

She opened up about the experiences in a tweet inspired by the 'Me Too' movement, which encouraged women to identify themselves as victims of sexual harassment or assault following the Harvey Weinstein scandal.

Nassar is currently in prison in Michigan after pleading guilty to possession of child pornography in July. He is still awaiting trial on separate criminal sexual conduct charges in addition to being sued by over 125 women in civil court who claim he sexually assaulted them.

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Olympic gold medalist McKayla Maroney (pictured center at the 2012 Olympics after the team won gold) named convicted sex offender former USA gymnastics doctor Larry Nassar as her repeat abuser from the age of 13 until the left the sport last year

USA Gymnastics shared this photo of Maroney and Nassar, her abuser, in 2013

Nassar is currently in prison in Michigan after pleading guilty to possession of child pornography in July. He is still awaiting trial on separate criminal sexual conduct charges in addition to being sued by over 125 women in civil court who claim he sexually assaulted them

Maroney, pictured above in recent years, said Nassar, who spent nearly 30 years as an osteopath with the USA Gymnastics program, molested her for seven years. The abuse happened at many high-profile competitions, including the 2012 London Olympic Games, where she won gold and silver medals

Several former athletes have accused Nassar of inserting un-gloved fingers into their bodies and fondling their breasts.

Maroney claims that Nassar, who spent nearly 30 years as an osteopath with the USA Gymnastics program, first molested her when she was 13 at a National Team training camp in Texas.

'Dr. Nassar told me that I was receiving "medically necessary treatment that he had been performing on patients for over 30 years",' Maroney said of her abuse.

'It seemed whenever and wherever this man could find the chance, I was 'treated',' she added. It happened in London before my team and I won the gold medal, and It happened before I won my Silver.'

Maroney claims that the worst abuse happened during the 2011 world gymnastics championships in Tokyo.

She wrote that Nassar had given her a sleeping pill on the flight to the Japanese city, and she didn't wake until she was in his hotel room, alone, where he was performing a 'treatment'.

'I thought I was going to die that night,' Maroney wrote.

Maroney offered a number of ways to end abuse and bring awareness to the issue, including holding people and organizations accountable and having zero tolerance for such incidents.

Maroney, 21, opened up about the experiences in a tweet inspired by the 'Me Too' movement, which encouraged women to identify themselves as victims of sexual harassment or assault following the Harvey Weinstein scandal

McKayla is also famous for pulling a 'not impressed' face after winning silver in the vault during the London games when she was favored for the gold

The USA Gymnastic team is pictured above during the London Olympic Games in 2012. Maroney is circled in the front row, while Nassar is circled in the back row

Maroney claims that Nassar molested her more than once during the 2012 London Olympics. They're both pictured above on a visit to the USA House at the Royal College of Art in London in 2012

Nassar, meanwhile, will be sentenced November 27 in federal court after pleading guilty to three child pornography charges in an unrelated case.

He is still awaiting trial on criminal sexual conduct charges in addition to being sued by over 125 women in civil court who claim he sexually assaulted them.

The disgraced doctor, who treated elite US gymnasts as Olympic team physician from 1996 to 2015, has pleaded not guilty to the assault charges and the dozens of civil suits filed in Michigan are currently in mediation.

Maroney of the United States poses with the gold medal after helping the United States win the Artistic Gymnastics Women's Team final at the London 2012 Olympic Games

In a week of hearings in late June, witnesses testified that Nassar, using his position as a team doctor, molested and penetrated girls with his fingers under the guise of providing medical care and helping spinal alignment.

'He convinced these girls that this was some type of legitimate treatment,' the prosecutor said. 'Why would they question this gymnastics god?'

The case involves seven women or girls, although dozens of others have also accused him of sexually assaulting them and are suing him in federal court.

A 16-year-old, who was abused while seeking treatment for an injured heel, described the doctor as being 'quite sweaty' during the alleged assault and 'into it' but did not have an erection, according to MLive.

She said he also touched her labia majora, clitoris and the inside of her vagina while rubbing the thigh of the leg that had a painful heel.

She said she came forward after reading other gymnasts' accounts last year in an Indianapolis Star story about Nassar.

Another 16-year-old girl had testified on May 12 that she went to Nassar to help her back, but she said he never indicated that he would be touching her private areas with ungloved hands.

Another alleged victim, 18, said that while the doctor went inside of her vagina with his fingers he peppered her with questions such as 'Does this feel better? Does this take your pain away?'

Maroney claims that Nassar molested her for years, starting at her first National Team training camp in Texas. She said that the worst abuse happened during the 2011 world gymnastics championships in Tokyo (pictured above)

She wrote that Nassar had given her a sleeping pill on the flight to Tokyo, and she didn't wake until she was in his hotel room, alone, where he was performing a 'treatment'. Maroney is pictured above at the 2011 World Championships in Tokyo

She also said he opened her rectum with tape but didn't touch it, and told her he did this for all the Olympians. She said she's having a hard time concentrating on her senior year in high school because of the trauma.

Several alleged victims have come forward to say that Nassar abused them, including Team USA gymnasts.

Sydney Olympics bronze medalist Jamie Dantzscher, US national rhythmic gymnastics champion Jessica Howard and US team gymnast Jeanette Antolin revealed the allegations of abuse by Dr Larry Nassar on 60 Minutes in February.

'He would put his fingers inside of me and move my leg around,' Dantzscher told the program. 'He would tell me I was going to feel a pop and that that would put my hips back and help my back pain.

'It happened all the way to the Olympics in Sydney, until I was 18.'

Dantzscher filed a lawsuit against Nassar in California last September as 'Jane Doe', but gave up her anonymity for the 60 Minutes interview.

Howard, who was the national rhythmic gymnasts champion from 1999 through 2001, said she had a severe hip problem when she was 15 and USA Gymnastics suggested she go to a camp called Karolyi Ranch to work with Nassar.

'He started massaging me. And he had asked me not to wear any underwear. And then he just continued to go into more and more intimate places,' she said.

'I remember thinking something was off but I didn't feel like I was able to say anything because he was, you know, this very high-profile doctor. And I was very lucky to be at the ranch working with him.'

The Karolyi ranch near Houston, Texas is an extensive training camp for Team USA gymnasts run by coaches Bela and Martha Karolyi.

Larissa Boyce (left), now 36, revealed how she was one of the first to accuse Team USA Gymnastics doctor Larry Nassar of sexual abuse when she was 16 years old (right), but she was ignored for decades before dozens of other victims came forward

Sydney Olympics bronze medalist Jamie Dantzscher (pictured) was first seen by Nassar at age 13. Detailing her alleged abuse by Nassar, she said: 'He would put his fingers inside of me and move my leg around'

US national rhythmic gymnastics champion Jessica Howard (right) and US team gymnast Jeanette Antolin (left) have also alleged abuse at the hands of Nassar

The athletes would stay in cabins for the duration of the camp, which is where Nassar was on hand to treat the girls.

Antolin, a US team member from 1995 to 2000, said she only realized last year what she thought was treatment had been abuse.

'It was like a light bulb went off,' Antolin said. 'I trusted this man. Just knowing how vulnerable I was as a kid, to not know something like that would be inappropriate, just ruined me.

'I remember being uncomfortable because of the area. But in my mind, I was like: "If this helps, I'll do anything".'

Many ex-athletes accusing Nassar of crimes say he was empowered by an environment in elite gymnastics where complaints or signs of injury could jeopardize Olympic dreams.

The president of USA Gymnastics, Steve Penny, resigned in March after repeatedly being urged to quit for allegedly being slow to notify authorities about sexual abuse allegations in the organization.

The organization launched an independent review of its policies in the wake of the allegations against Nassar and reporting by the Indianapolis Star that highlighted chronic mishandling of abuse allegations against coaches and staff at some of its over 3,500 clubs across the country.

In June the federation immediately adopted 70 recommendations proffered by Deborah Daniels, a former federal prosecutor who oversaw the review.

Nassar served as the US gymnastics team's doctor through four Olympic Games. In a week of hearings in late June, witnesses testified that Nassar, using his position as a team doctor, molested and penetrated girls with his fingers under the guise of providing medical care

The new guidelines require member gyms to go to authorities immediately, with Daniels suggesting USA Gymnastics consider withholding membership from clubs who decline to do so.

The organization also named Toby Stark, a child welfare advocate, as its director of SafeSport. Part of Stark's mandate is educating members on rules, educational programs, reporting and adjudication services.

Nassar served as the US gymnastics team's doctor through four Olympic Games.

The case cast a dark shadow on the country's vaunted youth gymnastics program, which has produced a steady stream of world and Olympic champions.

Reacting to the news earlier this year, USA Gymnastics said it was 'outraged that a physician would exploit his patients in the manner alleged', and described Nassar's behavior as 'appalling and heartbreaking'.

It added it had 'cooperated fully with the FBI and other law enforcement agencies'.

USA Gymnastics, the US Olympic Committee, and some of the country's most prominent gymnastic clubs known for training Olympic champions, have nevertheless been sued for allegedly hiding and protecting sexual abusers, including Nassar.

Also sued is Michigan State University, where coaches and trainers were allegedly told about Nassar's abuse as early as 1999 but took no action.