Calls for mothers to stop sleeping with their newborn children are being ignored by some hospitals and birthing centres, with staff at one saying it's better to teach mothers how to do it safely than ignore the popular practice.

Last week, coroner Gordon Matenga warned of the dangers of parents co-sleeping with newborns following the "avoidable" death of a 3-week-old boy sleeping with his mother on a pullout couch.

Mr Matenga said the advice on bed-sharing was strongly debated, with some arguing the risk of death was low and the practice encouraged bonding and assisted with breastfeeding.

However, he said co-sleeping deaths were avoidable and asked for his warnings about the risks of doing so to be made public.

"The information is certainly available, but it can be difficult fighting against traditional values and methods," he said. "The battle must, however, continue to be fought."

Mr Matenga's comments followed similar warnings from two coroners last year after the death of five babies.

One coroner went as far as to urge the Ministry of Health to make it clear that babies under 6 months should not co-sleep.

However, despite such requests and warnings, co-sleeping remains widespread in many hospitals and birthing centres.

In Auckland, most of the hospitals and birth centres the Herald spoke to recommended babies sleep in their own beds but had guidelines in place if parents wanted to co-sleep anyway.

Some of those guidelines simply provided advice on how to do so safely. Waitakere and North Shore hospitals went as far as insisting a "responsible adult" supervised the sleeping mother at all times.

However, at the Helensville Birthing Centre, staff take a different approach, believing that many women want to co-sleep so it's better to teach them how to do so safely.

"Our belief is that people go home and co-sleep with their babies so we do talk to them about how to do it safely," said clinical manager Michelle Nasey.

"I think there's a lot out there in terms of saying, 'You mustn't do it, you mustn't do it', but the reality is people go home and do it and I think it's terrible people aren't told how to do things safely."

Providing new mothers don't fall into any of the high-risk categories - such as having smoked during pregnancy or taken drugs, alcohol or medicine that might reduce awareness - co-sleeping with newborns is encouraged.

In an attempt to increase safety, the centre has recently introduced side-car cots, which clip onto the side of each bed, allowing babies to sleep next to their mothers but in a separate space.

Middlemore Hospital's maternity wing has also recently trialled a similar cot and both centres say they have been hugely popular with new mothers.

Mothers the Herald spoke to said there were varying responses from hospital staff and midwives throughout the country about co-sleeping - from ignoring it to actively pushing it, even when it wasn't wanted.

One mother, who went to a birthing centre, said she was upset because her son wouldn't sleep, so a midwife recommended taking him to bed.

"Despite my saying I was against this, it was the only thing that she kept suggesting ... to the point I got angry at her."

Another mother, Demelza George-Franzmayr, said that when she decided to co-sleep, it felt like it was a "let's not talk about it" issue.

"In hospital, I was not discouraged from sharing, but neither was I blatantly encouraged to do it either."

Hastings mother Nadine Gaunt, who co-sleeps with her 9-month-old, said the best thing that could happen was for all hospitals to educate women who did want to sleep alongside their baby on how to do so safely.

"The hospitals just need to give the advice.

"They don't need to advocate or not, just give the advice."

Co-sleeping Guide
* It is known to increase the risk of death in some circumstances so babies should sleep in their own space until six months old.

* It is particularly dangerous if the mother smoked during pregnancy, or any adult in bed has been drinking, taking drugs or medicines that might reduce their awareness, or is excessively tired.