Mothers have told a Senate committee that they and their babies will miss out if the government goes ahead with a crackdown on paid parental leave.
Lieutenant Commander Sandra Croft has fought for Australia and now she is fighting to be able to spend six months at home with her baby.
The military has a rigid maternity leave system requiring women to take either 14 weeks at full pay or 28 weeks on half pay.
The half-pay option would leave Lt Cmdr Croft with just $120 a fortnight after bills, she told a Senate committee on Tuesday.
"You just can't live on that," she told senators examining the government's plan to crack down on so-called double dipping of government and employer paid parental leave schemes.
The only reason she could take six months off with her son was because of the taxpayer-funded minimum wage leave scheme topping up that $120.
Lt Cmdr Croft is now contemplating having a second child.
If the government passes its changes, which will cut women off from the taxpayer-funded scheme if their employer offers leave worth $11,800 or more, she will only be able to spend 14 weeks at home with the new baby.
"I just can't imagine leaving for work at seven in the morning and not getting home until six o'clock at night and having that three-month-old baby bond with somebody else," Lt Cmdr Croft said.
Another mother, Rachel Green, who like Lt Cmdr Croft is a member of advocacy group The Parenthood, told the committee women's salaries mattered to family budgets.
"To have, in my case, 70 per cent of the household income disappear for a time, that creates a massive hole," she said.
"Every bit of support to be able to stay afloat is essential."
Ms Green said it was distressing on her first Mother's Day back in May to hear ministers describe her as a rorter and double dipper because she intended to access all the leave she was legally entitled to.
She warned of a "stampede on childcare places" if women were forced back to work earlier because they couldn't afford to have as much time off.
Those concerns are shared by unions and advocacy group Women On Boards, which said the measures could force women into work earlier or create a shortfall in childcare places.
Mums may decide it's too hard to get a place and end up falling back on parental welfare payments.
"That's very undesirable," chair Ruth Medd said.
Australian Chamber of Commerce and Industry boss Kate Carnell believes the government won't achieve most of the billion-dollar saving from the changes.
She conceded women working for small businesses were less likely to get parental leave.
Ms Carnell said employers were likely to rejig the way they pay parental leave to employees.
"They're not going to sit back and allow their female employees to lose $11,800 and say well that was just a bit bad," she told ABC radio ahead of the inquiry.
AI Group warned the changes could make it difficult to determine if employers were legally obliged to pay leave.
The proposed changes could also create industrial claims for employers to meet the cost of the government's leave payments, it added.