"We are all abused," she said on Twitter, claiming the group were made to "sleep with whoever they say".
The band, led by Nicole Scherzinger, said they "were not aware of Kaya's experiences" and offered her support.
However, they firmly denied that the remaining members had been abused.
"We cannot stand behind false allegations towards other group members partaking in activities that simply did not take place," they said.
"To liken our professional roles in The Pussycat Dolls to a prostitution ring not only undermines everything we worked hard to achieve for all those years but also takes the spotlight off the millions of victims who are speaking up and being heard loud and clear around the world," the statement continued.
"We stand in solidarity with all women who have bravely spoken publicly of their horrific experiences of abuse, harassment and exploitation."
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