Gemma Edney put her oldest son Gibson into childcare when he was just three months old. She was able to stay home longer with Tavia and Rafferty. But whatever a mother does, she says, people will judge her.

A boom in daycare is seeing children spend up to 10,000 hours in care by the time they start school. A major childcare report shows increased risk of childhood respiratory illness, obesity, aggression and hyperactivity.

The new generation of babies placed in childcare face behavioural and health risks, says a major new scientific review.

It is a weighty blow in the contentious fight over whether parents should puts their kids in care – a debate that puts mums and dads on the instant defensive as they battle yet another dose of parental guilt.

The Brainwave Trust has produced the report to help parents navigate conflicting research and raise questions over whether the system is working against children.

READ MORE:

* Childcare workers slam 'factory farming children'

* Early childhood complaints on the rise

* Toddlers spend up to 11 hours in daycare

Despite the Trust's independent scientific credentials, the research has been embraced by family values lobbyists, and condemned by the childcare industry as "scaremongering".

>> The review says kids who attend childcare are more likely to display: aggression, hyperactivity, disobedience and problems with attachments

>> Health risks include higher rates of: antibiotic use, respiratory illnesses and obesity.

Christchurch mum Gemma Edney was forced to put her three-month-old son into care to pay the bills.

"It was also sanity points for me because I was a single mum.

"The centre encouraged social interaction and learning on a spectrum that I didn't know about. It was a big resource."

Her son later attended full-time care. Her two other children went into part-time care at 8-months and 2-years-old.

Parents feel the the judgement, no matter what they decide, she said.

Edney knows. She has been a stay-at-home mum and a working mum.

"If you tell people you work fulltime they turn their nose up, but if you say you're a fulltime mum they do the same."

For two years, the Brainwave Trust sifted through stacks of research, some dating back decades, to find an answer to a common question from confused parents: What is the effect of childcare on babies, infants and toddlers?

It is not easy reading for the increasing number of parents with babies in care.

Brainwave Trust researcher Keryn O'Neill said they don't want to make parents feel guilty, but can't fudge the facts for fear of making people feel bad.

"It's not simple. There's no one answer, but we've come up with over-arching messages.

"One of those is that while there can be benefits for children from three years old, there can be risks for children under three.

"Those risks increase the younger the child is."

Some of benefits of childcare have also been over-stated or the positive research is irrelevant to New Zealand's centres, O'Neill said.

YOUNG CHILDREN VULNERABLE

So what are some of the causes of increased risk factors?

A child, particularly aged under two, is more vulnerable to the effects of childcare including the stress hormone, cortisol.

"We have a typical daily rhythm where the cortisol levels are usually highest when we wake up and gradually drop over the day.

"That pattern becomes evident in the first few months of life. For children in childcare, especially in full-time care, they don't get that drop in the same way. The patterns change across the day."

However, all the long term implications are not known, she said.

There was limited research on under-twos since the growth in this age group in care was recent phenomenon.

The proportion of one-year-olds attending childcare jumped from 15% to 24% in the decade to 2009. That number would be even higher now, O'Neill said.

A baby in continuous full-time care can spend up to 10,000 hours in childcare by the time they start school – more than all their primary and intermediate hours combined.

It was time to discuss the factors pushing parents back to work, she said, including the length of paid parental leave and employers willingness to be flexible.

'MUST TRY HARDER'

Education experts and a child advocate have welcomed the report as a chance for debate.

Victoria University childhood studies professor Carmen Dalli said New Zealand was not doing enough for under-twos.

"In many centres the least qualified adults are put in with the babies because people still have the view you don't need to know much."

Childcare centres should be required to have all qualified teachers and one teacher for every three children aged under two.

For many parents, the choice to send children into care was out of necessity.

Unicef NZ national advocacy manager Deborah Morris-Travers said there were parents who didn't have the same choices due to financial pressures and rising housing costs.

"Hopefully parents will look at this information and see there is real merit in spending as much time with their child in the early years as they can.

"If they do need to be in childcare, shorter periods are better."

About 76,000 children aged under three are in childcare, some of them full time.

Morris-Travers said primary school teachers had been reporting higher levels of anxiety among children as the numbers in childcare grow.

The Government should heed the Brainwave review and focus on quality control and regulation in childcare centres, rather than simply pushing for more bums on seats.

"It's just not good enough to have short-term objective of rushing parents back to work."

Like other child advocates spoken to, she called for minimum 6-months parental leave and more financial support for parents of young children.

"We're not investing enough in families to give them that time at home."

Family values lobbyists Family First hailed the report.

Family First director Bob McCoskrie said everyone was scared to touch the topic for fear of being scalded. "No one wants to make parents feel bad, but parents deserve to make an informed choice."

Childcare was too often thought about in terms of benefits to adults rather than the effect on children, he said.

"We've persuaded ourselves that professionals can look after our babies and toddlers and parents are far more benefit to society by working.

"It is a really dangerous message."

The childcare industry slammed the report. Parents shouldn't rush to pull youngster out of care after reading the report, according to Early Childhood Council chief executive Peter Reynolds.

"That sort of stuff is scare-mongering and increasing the level of guilt parents will feel when they have to place the kids in care while they pay the mortgage."

Childcare can help children in their development, including their language and learning, he said.

"It's a place where kids are happy, safe, learning and getting something out of their experiences.

"And parents are confident they are getting something out of it."

WHAT ABOUT THE PARENTS?

Parents, the biggest players in this debate, all agreed their children were happy and learning in care.

A number of parents spoken to said their under-twos were picking up new skills, socialising with other children and were happy in care.

Auckland mum Kelly Vize enrolled her son into part-time daycare when he was 15 months old.

"From the first day he loved it. It's purely for him rather than me. It's for his interaction. Of all of the toys he could play with, another kid is always his first choice."

As for Edney, she now works part-time while her two youngest are in childcare and her son is at school.

She had no regrets, she said, and has seen no damaging effects on her children.

And while she was a single mum she had little choice but to work.

The government was also standing by its own research sources which support childcare.

Education minister Hekia Parata said parents play the most important role, but childcare can make a contribution.

"The advice to me as Minister from education experts is that quality early childhood education sets kids up to do better in education and in life.

"Nothing I've seen as a parent or Minister has caused me to question that advice."

On the policy side, paid parental leave is being extended from 16 to 18 weeks next month.

New Zealand has the third lowest teacher:child ratios in the world.

However O'Neill, from the Brainwave Trust, said many caring, well-informed parents still felt totally confused.

In some social circles it was expected parents would return to work and stay-at-home mums were belittled, she said.

In other social groups, parents were judged for sending their child into care, no matter their motivations.

It was no wonder childcare had become a firestorm of controversy, with political, religious and economic agendas stoking the debate.

"That's where Brainwave has a contribution to make because we're independent. We don't have political or religious affiliations. We don't stand to gain or lose ourselves by putting the information out there.

"We're looking at it from the child's perspective because they have the least voice in this."

RESEARCH FINDINGS

Children can benefit from early childhood education when:

* They are three or four years old

* They attend part-time

* The care is high-quality and stable

Children are more at risk at early childhood education when:

* Children are younger than three-years-old, particularly babies

* Increased time at childcare

* When the care is poor quality or unstable

What makes a quality childcare centre:

* Low teacher to child ratio. Experts say 1:3 or less is best for under-twos

* Fully qualified teachers

* A space to play and interact, but also an area for quiet time

* Warm, respectful and compassionate teachers

* Children not being left to cry

* Reasonable noise levels so a child isn't overwhelmed