Labor says the government should restore the annual women's budget statement after a new analysis showed some women face an effective marginal tax rate of 100 per cent as a result of the federal budget.
The call came as officials from the Office of Women, which sits within the prime minister's department, revealed Treasury had done modelling on impact of the budget on women's effective marginal tax rates.
Effective marginal taxation rates (EMTRs) measure the proportion of each extra dollar of earnings that is lost to both income tax increases and decreases in government benefits.
The study by the National Foundation for Australian Women showed a combination of the Medicare levy increase, cuts to family tax benefits and making low-income earners pay back university debts earlier could be devastating for some women.
"These changes could lead to effective marginal tax rates of possibly 100 per cent or higher for some women, particularly as Family Tax Benefit Part A begins to decrease at $51,903," the Gender Lens on the Budget report said.
Office for Women senior official Lin Hatfield-Dodds told a Senate hearing on Monday the Treasury department had produced modelling on EMTRs for women.
"We will be accessing at least the policy work on that, if not the modelling," she said.
Asked why the work was not accessed before the budget, Minister for Women Michaelia Cash said the office was in "constant discussions" with other portfolios about the impact of policies on women.
Senator Cash said issues to do with EMTRs for women would be dealt with in a report relating to Australia's G20 commitments.
Under Australia's G20 presidency in 2014, leaders agreed to the goal of reducing the gender gap in workforce participation rates by 25 per cent by 2025 - adding about 200,000 women to the workforce.
Labor senator Jenny McAllister said the study showed why the women's statement should be restored to the budget, having been abolished under the Abbott government.
"Unless women's interests are specifically considered when government makes economic decisions, women lose out," she said.
Labor senator Patrick Dodson said there should also be a greater focus on the conditions experienced by indigenous women.
"Absolutely. I think the conditions of women, particularly indigenous women, who are being over-incarcerated, there should be a focus on that," he said.
"There's something that's not functioning. Therefore supports are lacking for families, for women in particular. Domestic violence, we know, is out of control and there has to be support through legal services and other counselling services."
