Three women who attend Yale University sued the school and nine all-male fraternities Tuesday, seeking to force the social organizations to admit women in response to alleged sexual assault, harassment and discrimination.

The class-action lawsuit, filed in federal court in Connecticut, calls for a sweeping order banning fraternities from considering gender in admission decisions; fully integrating women in fraternity governance and alumni networks; and requiring Yale to prohibit student organizations — both on campus and off — from engaging in discrimination and harassment.

The three students also say women are being shut out of the social and economic benefits offered by all-male fraternities, including access to vast alumni networks that can help land coveted jobs. While there are sororities, their power and influence pales in comparison with fraternities, the lawsuit says.

"It's not only breeding a very toxic sexual culture but also is giving undue economic and professional benefits to the male fraternity members," said one of the plaintiffs, Ry Walker, a 20-year-old junior from New York City majoring in astrophysics and African-American studies.

A Yale spokesman, Tom Conroy, said he did not have a comment on the lawsuit. But he pointed to a message shared last month by Yale College Dean Marvin Chun who described a review of allegations of a sexually hostile climate at the Delta Kappa Epsilon fraternity and the school's efforts to bring about more social opportunities for students on campus.

An attorney for the fraternities, Joan Gilbride, said the students' accusations are baseless.

The other two plaintiffs are junior Anna McNeil and sophomore Eliana Singer. Their lawyers say they believe this is the first-ever lawsuit by students against a university seeking to "gender integrate" fraternities.

All three plaintiffs said they were denied membership to fraternities, were groped at fraternity parties and know other students who were sexually assaulted or harassed at frat parties.

The three students said they complained to Yale about sexual misconduct and discrimination by fraternities, but school officials offered them "no meaningful assistance or relief."

"Yale is a microcosm of the ongoing epidemic of sexual harassment and assault at all-male fraternities," the lawsuit says. "Many Yale students now accept and assume that female undergraduates risk sexual harassment and assault by attending fraternity parties."

To help prevent sexual misconduct, the lawsuit asks a judge to order that co-ed "sober monitors" be appointed for each off-campus event and party to ensure safe levels of alcohol consumption and intervene to prevent sexual assault and harassment. The plaintiffs also want paid bouncers at every fraternity event and party for crowd control and nondiscriminatory event admission.

The defendants include the local and national chapters of fraternities including Alpha Delta Phi, Alpha Epsilon Pi, Chi Psi, Delta Kappa Epsilon, the Leo fraternity, Sigma Chi Theta Upsilon, Sigma Nu, Sigma Phi Epsilon and Zeta Psi.