A prominent Labour MP says Jared O'Mara should be suspended from the party while claims he made misogynistic and homophobic remarks are investigated.
Former shadow education secretary Lucy Powell made the comments on ITV after Mr O'Hara was accused of making offensive comments in March 2017.
Labour has launched an investigation into his behaviour.
The Sheffield Hallam MP apologised for remarks made online in 2002 and 2004, but denies the more recent allegations.
On Monday Mr O'Hara resigned from the women and equalities committee after political website Guido Fawkes unearthed offensive comments made by the 35-year-old MP.
Then on Tuesday, Sophie Evans told the BBC's Daily Politics she had met Mr O'Mara on a dating app and there had been "no hard feelings" when things didn't work out between them.
But in an incident in March 2017 Mr O'Mara, who was DJing in a nightclub, made comments to her that "aren't broadcastable" and called her an "ugly bitch", she said.
Mr O'Mara said this was "categorically untrue".
Ms Powell, MP for Manchester Central, told ITV's After The News: "One of the key questions you're asked when you become a candidate for the Labour Party – and you have to sign a contract to say this – is there anything in your past that would bring the party into disrepute?
"And I don't understand, in all honesty, how Jared could have signed that paper. That's why I think he should be suspended while that investigation is taking place."
Liberal Democrat leader Sir Vince Cable has also called for Mr O'Mara to have the Labour whip removed.
But shadow chancellor John McDonnell said: "He has apologised for what we knew yesterday. He issued a profuse apology.
"Any language like that we know is unacceptable and I'm hoping he will apologise for that."
The offensive comments published by Guido Fawkes included messages where he claimed singer Michelle McManus only won Pop Idol "because she was fat" and it would be funny if jazz star Jamie Cullum was "sodomised with his own piano".
More comments, involving homophobic language, then emerged dating back to 2002.