More than 150,000 Australian parents who want to work cannot because child care is expensive and hard to find.

The Federal Government is considering changes to the sector, which could include subsidising alternatives to childcare centres, such as nannies.

In the meantime, families who need two incomes to get by are relying on a patchwork of temporary solutions.

Shae Clavaerie used to work as a bookkeeper. Now, instead of wrestling with figures, she wrangles children.

"When I had my third child it was pointless for me to go to work and pay three childcare fees, so I had to think outside the square," she told 7.30 in her house full of pre-schoolers.

She now runs a family day care centre on Sydney's northern beaches, looking after four kids at once - just one of them hers.

She is one of 25,000 Australians who run family day care centres from their homes.

"I think family day care's just a lot more personal and for the children that are so young it's still a home environment," she said.

"There's only a few of them, it's not a million kids and it just builds them up with confidence before they hit the child care, kindies, or long day cares, wherever they decide to go.

"So I think it's a nice stepping stone for them. I really believe in family day care and I really believe in child care full stop."

Sector in 'crisis' amid $5.5bn cost to economy

For many parents, believing in child care is easier than finding it, something Assistant Minister for Education Sussan Ley acknowledges.

"Families tell me there's a crisis," she said. "Centre directors tell me there's a crisis."

The crisis is that there are too few child care places and the child care that is available suits only part-time workers.

So the Government commissioned a mammoth review of child care by the Productivity Commission, which will deliver its final report next month.

One of the Government's aims is to get more women back into the workforce.

"While we miss out on women's participation in workforce we miss out on their talent, their ingenuity, the contribution they make, the investment we in this country made in training," Ms Ley said.

"For every year they stay out [of the workforce], the economy loses billions for that group not participating."

It has been estimated that $5.5 billion is lost to the economy each year because parents who want to work cannot.

Professor of employment relations at the University of Sydney Marian Baird said without a better childcare system, the economy is missing out on some of its best workers: highly educated women in their early 30s.

"All our research indicates those women turn out to be very good mothers but also highly committed workers," Professor Baird said.

"The hardest years are the pre-school years. That's where tension is and that's why we need to support the childcare system."

Cheaper for family to fly in mother-in-law from UK

The only way new mother Simone Walker could get back to work after the birth of her son, Saxon, was to bring in help from overseas.

"We decided to fly my mother-in-law over here," she told 7.30.

"It was cheaper to pay for a flight and pay for her expenses to live with us than to try and find day care for him."

Simone Walker flew her mother-in-law Jackie (R) over from the UK to care for her son Saxon.

Saxon's grandma, Jackie, now calls the western Sydney suburb of The Ponds home rather than the United Kingdom.

"I was going to be spending 70 per cent of my pay getting to work and covering the cost of having Saxon taken care of," Simone Walker said.

Childcare centres and family day care cost more than $100 a day, meaning even a three-day-a-week job can end up costing parents $15,000 a year in fees for each child.

"Once they do the calculations of child care costs, reduced benefits, increased taxation, you end up in a situation where they think would it be better if they stayed at home for that period of time," Professor Baird said.

Jackie will head back to Britain next year - by then Saxon will hopefully be in a childcare centre.

"I would really like to be able to leave the house one or two days a week, be able to interact with adults and also keep up my skills," Ms Walker said.

"I didn't want to be out for too long, didn't want to lose skills. I didn't want to have the issue of being a mum trying to get back one foot in the door."

The Government has indicated it will adopt some of the Productivity Commission's draft recommendations, such as simplifying childcare assistance payments and subsidising in-home care, which includes nannies.

"If you've got two or maybe three children, does it really make sense to pile them into the car, take them to child care, drop them off, do the commute to work, do it all again at the end of the day and arrive home with the whole family exhausted?" Ms Ley said.

"It doesn't. But what I've said is, if we go to in-home care, we will make sure that it's within the formal regulated system.

"We will not be paying nannies to unstack dishwashers, or [be] home help, as some people have put it."