Former Liberal staffer Brittany Higgins is preparing to make a formal complaint to police alleging she was raped by a colleague inside Parliament House.
Ms Higgins will speak to police on Wednesday after going public with the sexual assault allegation last week.
Three more women have since come forward saying they were also assaulted by the man.
Defence Minister Linda Reynolds, who employed Ms Higgins at the time of the allegations, has been under intense pressure over her response.
She was due to face questions from the media for the first time since the story broke at the National Press Club in Canberra on Wednesday.
However, the minister has been admitted to hospital and is taking medical leave.
Her speech has been cancelled.
Ms Higgins says she originally felt pressured not to pursue an investigation, fearing her job would be jeopardised.
Senator Reynolds insists she always prioritised Ms Higgins’ best interests.
The minister has been forced to correct the record as to how many times she met with police about the allegations.
She did not tell Prime Minister Scott Morrison of the allegations.
Communications Minister Paul Fletcher concedes he would have handled things differently.
“In light of all of the circumstances and the way that these issues have developed over recent weeks, I think that that will be a practice that would be expected,” Mr Fletcher told the ABC.
“But I want to say that I think that Minister Reynolds has sought to conscientiously deal with this matter.”
Meanwhile, Home Affairs Minister Peter Dutton is refusing to say if federal police followed standard practice and informed his office of the allegations.
The prime minister continues to face questions about when he found out about the incident, but insists it was not until last week.
There are four inquiries into different aspects of the culture inside Parliament House, what the prime minister’s office knew about the allegations and complaints processes.