Women who don’t have children often leave jobs because they feel exploited by practices that favour parents.
Psychotherapist and author Jody Day told Newstalk Breakfast the problem is more often than not down to bad HR management.
She said it's an issue that many workers without children, either by choice or by circumstance, come across.
"I've been hearing women... talk about this for over a decade," she said.
Ms Day said this issue is not about "a fight between women...really, it's workplaces not managing this well enough".
"There's a lot of kind of social pressure, particularly between women, that you let the parents in your office have that time,” she said.
"If you stand up for fairness, you're seen as bitter or unsisterly.
"It can be quite subtle to go, 'Actually I think it's my turn' and they'll go 'But you don't have kids?'"
'Less valuable as humans'
Ms Day said childless people need to start speaking up, but it's not easy.
"That's really hard because of... people going, 'That's not very supportive of you'.
"It can be really challenging to do that.
"Pronatalism tells us that people without children are less valuable as human beings, they're less grown up, their less realised.
"If you've internalised those beliefs, it's unlikely that you're going to go marching into HR and say, 'I'm of equal value and I want my time off too'.
"A lot of people leave workplaces like that because of these unfair practices, which are basically HR not getting organised enough to make sure there's enough cover".
'Your life outside work'
Ms Day said there is no real issue if parents want certain time off, unless it clashes with others.
"I think we can understand that parents would want to spend Christmas with their children, I don't think anyone has any problem with that," she said.
"I think it's when those kinds of things come at the detriment to people in the office that don't have children, it starts to become a problem.
"If you're in a profession like nursing, for example, where there have to be people working on Christmas Day, on New Year's Day, you can go years without being able to take that day off".
Ms Day said there is a perception that a childless person's life outside work "is not as important as someone who has children", while those who are single can also get an unfair share of work.
"A lot of this falls heavily on those who are both single and without children, with the single people in the office being given the anti-social hours, the long work trips away because, 'Sure they don't really have a life'" she said.
'All of us have value'
Ms Day said reducing the value of those without children is unfair.
"I don't think there's anything wrong with supporting families and seeing the benefit of families to society, but we've got more than enough people," she said.
"I think to make families the most important thing by reducing the value of those without children - who also pay taxes, which support all the hospitals and schools that other people's children need - I think it's really important to think that all of us have value in civic society, not just families.
"I think you only have to look at the phrase 'As a mother' in front of absolutely anything, even if it's nothing to do with parenting, to see how being a parent gives you status," she added.
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