The Gillard government will launch an inquiry by the Australian Human Rights Commission into the treatment of women in the workplace, marking a return to the vexed issue of gender equality by the Prime Minister.

To be revealed on Saturday, the inquiry follows sustained pressure from the ACTU and follows last week's speech by Julia Gillard warning voters that women's voices would struggle to be heard and that access to abortion would be threatened if the Coalition won office.

"I want us to be a nation where [there is] equal opportunity for everyone at every time in their life": Prime Minister Julia Gillard. Credit:Alex Ellinghausen

The speech sparked a heated week-long debate about gender issues fuelled by revelations of sexual abuse in the Australian Defence Force, the leaking of a sexist and offensive menu targeting Ms Gillard and radio announcer Howard Sattler being sacked after demanding Ms Gillard answer whether her partner Tim Mathieson was gay.

Ms Gillard's poll rating slumped by 7 percentage points among men while rising only by 1 point among women.