Video report by ITV News political correspondent Emily Morgan
Labour MP Jared O'Mara has had the whip suspended while claims that he called a constituent an "ugly bitch" just months before his election are investigated, the party said.
The move follows the announcement on Tuesday that the party had launched an investigation into the Sheffield Hallam MP's comments and behaviour.
A party spokeswoman said: "He has had the whip suspended while the investigation is carried out."
The MP "categorically denies" claims made by his Sheffield Hallam constituent Sophie Evans about an incident in March this year.
Ms Evans said Mr O'Mara made offensive remarks to her in a Sheffield nightclub that he DJs at during a night out..
She alleges Mr O'Mara called her an "ugly b****" after an altercation between him and her colleague.
"It was misogynistic, it was transphobic, and it was angry and aggressive," Ms Evans told Good Morning Britain.
"I just wanted people to know what he was like. I wanted people to know this is the man representing you."
On Monday O'Mara resigned from his position on the Commons Women and Equalities Select Committee after it was revealed he joked about having an orgy with members of the pop group Girls Aloud in 2004.
As well as comments about Girls Aloud, O'Mara had claimed Michelle McManus only won Pop Idol "because she was fat" and suggested it would be funny if jazz star Jamie Cullum was "sodomised with his own piano".
The MP apologised for the offensive comments, which were first revealed by the Guido Fawkes website.
O'Mara ousted former deputy prime minister Nick Clegg in the June election to become MP for Sheffield Hallam.