Allegations of misconduct dated to the 1990s, but Dr. Tyndall continued to see thousands of patients as the center’s primary gynecologist. He was first suspended in 2016, after a nurse complained about him to the campus rape crisis center. After a yearlong investigation, university officials forced him out.

But they did not report the accusations to the California Medical Board. When their internal investigation was complete, officials said that the findings were a personnel matter and that there was no legal obligation to notify the state oversight board, which investigates doctors accused of misconduct.

The latest scandal at U.S.C. comes less than a year after the university was roiled by reports that the former dean of the medical school spent months partying with prostitutes and using drugs on campus. Before his resignation, he had been celebrated as a prolific fund-raiser and accomplished physician. The man chosen to replace him was forced to step down after reports surfaced that he had settled a sexual harassment case with one of his former researchers.

U.S.C. officials said they had received more than 100 complaints about Dr. Tyndall, either through a hotline or a website the university set up to receive complaints. (More than 350,000 students and alumni received an email Tuesday that included information about Dr. Tyndall and how to report any concerns.) About half the complaints received this week were anonymous and the majority were about comments that Dr. Tyndall made during exams, officials said.

In an interview with The New York Times, one woman cried as she recalled dialing into the hotline and recounting an appointment she had with Dr. Tyndall before graduating from U.S.C. in 2007. During a pelvic exam, she said, Dr. Tyndall inserted several fingers inside her and told her “you know what they say about tall women, right?” which the woman, who is more than six feet tall, took to mean she had a large vaginal opening. The woman, who is currently a lawyer and spoke on the condition of anonymity because she did not want to alienate current clients, said she did not report his comments at the time. Even now, she said, his remarks make her feel self-conscious during sex.