The Labor Party is being urged to preselect female candidates to replace a number of outgoing federal MPs, including former prime minister Julia Gillard.

The departure of Ms Gillard and several other ministers has put the ALP under pressure to find suitable replacements who have a strong chance of holding seats for the party.

Women within the Labor movement say the party should be doing more to meet its affirmative action target.

Tanja Kovac from the group EMILY's List, which campaigns to get more Labor women into Parliament, says this applies to the safe seat of Lalor vacated by Ms Gillard.

"What greater legacy could there be for a female Labor prime minister than for there to be a woman who follows in, a progressive woman who follows in her footsteps," she said.

As well as Lalor, three more seats have become vacant this week with the resignations of Stephen Smith, Craig Emerson and Peter Garrett.

It is understood the leading candidates for Mr Smith's seat of Perth and Dr Emerson's seat of Rankin are lawyer Tim Hammond and former chief-of-staff Jim Chalmers.

Under Labor's affirmative action policy though, women must be endorsed in 40 per cent of winnable seats - something Ms Kovac is keen to reinforce.

"The ALP is tracking below that target at the moment," she said.

"That's why we think it's really important that any seats that are now becoming vacant because of resignations and decisions by some fantastic Labor members not to stand in this election, that there be some consideration of women being preselected in those seats."

The issue of female representation was highlighted recently during the controversial preselection contest for Nicola Roxon's seat of Gellibrand.

Two women contested the seat but were defeated by the male candidate, Tim Watts.

And despite calls from senior female ministers to endorse a woman, Labor senator David Feeney is expected to win preselection for the safe seat of Batman over Mary-Anne Thomas from the Left.

In her final press conference as prime minister, Ms Gillard had this message for future female leaders:

"What I am absolutely confident of is it will be easier for the next woman, and the woman after that, and the woman after that and I'm proud of that," she said.