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If you or someone you know is suffering from abuse, please contact the National Sexual Assault Hotline at 1-800-656-4673.

More than 300 women have come forward in a new lawsuit that accuses Columbia University and the NewYork-Presbyterian/Columbia University Irving Medical Center (CUIMC) of covering up years of abuse by former OB-GYN Dr. Robert Hadden.

Hadden was sentenced in June to 20 years in prison for assaulting dozens of patients and enticing four victims to travel between states to engage in sexual activity.

"This is about the pain and betrayal that Columbia University, its administration and its trustees have caused," attorney Anthony T. DiPietro, who filed the lawsuit under the Adult Survivors Act on Tuesday evening, told Fox News Digital. "Whenever you see serial sexual predators at an institution — whether it's Columbia University, Michigan State, USC — the thing that all those places have in common is that the institution always knows. The institutions are the problem."

DiPietro added that he believes "there are women who have been walking around for a decade, 15 years, 20 years, carrying the burden and blaming themselves for being abused."

VICTIMS OF SEXUALLY ABUSIVE NYC GYNECOLOGIST ASK JUDGE TO KEEP HIM BEHIND BARS AS LONG AS POSSIBLE

Robert Hadden

Robert Hadden was convicted in a federal sexual abuse case. (AP Photo / Seth Wenig / File)

"That shouldn't happen," he said. "That's not fair."

Columbia reportedly waited months before notifying patients via letter that Hadden was no longer working for the hospital – and omitted the reason why – according to ProPublica, a New York City-based nonprofit for investigative journalism.

NY JUDGE SENDS FORMER OB-GYN ROBERT HADDEN TO JAIL, CONVICTED OF SEXUALLY ABUSING HUNDREDS OF WOMEN

A CUIMC spokesperson told Fox News Digital in a statement that it is "profoundly sorry for the pain that Robert Hadden’s patients suffered and his exploitation of their trust."

"The prosecution of Hadden that led to his conviction of federal crimes showed how he purposely worked to evade our oversight and engineer situations to abuse his patients," the spokesperson wrote. "We also deeply regret, based on what we know today, that Hadden saw patients for several weeks following his voided arrest in 2012. Columbia then banned Hadden from his medical practice, and he has not worked as a doctor for 11 years."

Robert Hadden sat at a table during court hearing

Dr. Robert Hadden was accused of fondling and performing oral sex on women in 2011 and 2012. (Jefferson Siegel / NY Daily News via Getty Images / File)

CUIMC's OB-GYN department has "revised existing policies, adopted new ones, and expanded resources to earn and maintain patients’ trust" over the past decade, the spokesperson added.

"The Department’s overriding commitment to patient safety is expressed through continuous evaluation and improvement of practices and services to create an environment where patients not only are safe — but feel safe," the CUIMC spokesperson said.

NEW YORK OB-GYN ACCUSED OF MOLESTING PATIENTS DID SO HIS ENTIRE CAREER, PROSECUTORS CLAIM

NewYork-Presbyterian/Columbia University Irving Medical Center referred Fox News Digital to Columbia University for comment. Columbia previously agreed to pay a $236 million settlement to some 200 victims who accused the doctor of sexual abuse.

Evelyn Yang, the wife of former 2020 presidential candidate Andrew Yang, was one of the first to publicly voice allegations against Hadden. She was DiPietro's first client, he said.

"Thank you," Yang wrote Wednesday on X, formerly Twitter, as Columbia students protested the school after allegations were made public. "Columbia med students also agree. Hundreds of them in their white coats protesting today, chanting ‘stop the cover-up’ and ‘notify the patients.’ Please listen to your own community @Columbia and do the right thing."

Trial evidence has suggested Hadden committed sexual abuse against dozens of victims — his patients — for more than 20 years, using his position as a doctor to make inappropriate comments, touch his patients in a sexual manner and give patients unsolicited advice about their sex lives, prosecutors said.

FORMER OB-GYN ACCUSED OF RAPING HUNDREDS HAS FACED THREATS, EXTORTION BY OTHER INMATES, ACCORDING TO LAWYERS

"Columbia University’s direct knowledge of, and involvement in, HADDEN’s abuse — and the institution’s ongoing cover-up — makes these cases even more disturbing than what we’ve seen happen at any other U.S. University to date," the lawsuit filed Tuesday states, adding that Columbia "knew as early as 1994 that Robert Hadden was a dangerous sexual predator, yet inexplicably allowed HADDEN to continue abusing and traumatizing female patients for two more decades."

Columbia University students protest in white coats

Columbia students protest outside the university Wednesday after a lawsuit accused the school of covering up years of sexual abuse allegations against former OB-GYN Dr. Robert Hadden. (Handout)

The lawsuit also accuses Columbia and other defendants of coordinating a "long-term coverup (sic) of Hadden's serial abuse for the purpose of deceiving and duping the Plaintiffs, and the public at large, into believing at varying times, and on countless occasions, that their employee, Robert Hadden had done nothing wrong, that he was simply providing legitimate and medically necessary OB-GYN services, and even that his sudden absence from the OB-GYN practice in 2012 was nothing out of the ordinary, and the result of his 'health issues,' ‘family issues,’ or his own ‘voluntary choice’ to close his private practice and retire."

NEW YORK OB-GYN ACCUSED OF MOLESTING PATIENTS DID SO HIS ENTIRE CAREER, PROSECUTORS CLAIM

DiPietro gave an example of one victim, an "international model," who visited Hadden for a Pap smear. Her results were normal, but Hadden told her to come back for additional Pap smears every two to three months, DiPietro said. The American Congress of Obstetricians and Gynecologists recommends women get Pap smears every three-or-so years.

"She thought he was just being thorough, or maybe she had cancer or pre-cancer. It was all bulls--t," DiPietro said. "He just wanted access to her body. That was it."

The lawsuit continues to allege that after Columbia initially learned of Hadden's abuse in 2012 and appeared to "have helped mobilize a criminal defense lawyer to assist" the doctor, they "permitted Hadden to return to their medical clinic the following week, so that he could continue sexually abusing even more women for the next six-weeks."

Robert Hadden

Dr. Robert Hadden, formerly of Columbia University, committed a "staggering" number of sexual assaults, prosecutors said. (AP Photo / Yuki Iwamura / File)

"It is not at all surprising that upon his return, Hadden continued his sick pattern of sexual abuse, including the abuse of pregnant women, recent mothers, and minor children," the complaint states. "All the while, the Columbia defendants knew full well that allowing Hadden to continue seeing patients was dangerous, reckless, harmful and wrong."

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In a September statement, university President Minouche Shafik and CUIMC CEO Katrina Armstrong commended the women who came forward against Hadden.

"Since Hadden last saw patients more than a decade ago, Columbia has worked to enhance the policies and processes in place to afford our patients a safe environment of care, and we remain committed to strengthening the safeguards that are essential for earning patient trust," they said. "Even still, it is difficult to reconcile this tragedy with the values that Columbia University is committed to upholding across our campuses."

The lawsuit filed on Tuesday is in the beginning stages of the litigation process, and Columbia will have a chance to respond to the allegations in court. There have been no findings of liability at the time of publication.