Waikato District Health Board nursing and midwifery director Sue Hayward said the use of amphetamines in pregnancy was associated with abnormalities in babies such as cleft lip while amphetamine-using mothers often suffered from high blood pressure.
"Babies born to these mothers are at high risk of dying and if they survive they are growth restricted (retarded) and the surviving babies' ability to grow is hampered for life."
Of the 32 properties police searched in the latest police operation, six contained children. That is on top of the 47 children found at 19 labs around the country this year.
More than 300 children nationwide have been found living in clan labs over the past four years, according to figures released to the Weekend Herald.
Other horrifying finds in the month-long Waikato operation included:
* meth bag and pipe next to baby formula in the kitchen;
* methamphetamine traces in the cot of a one year old;
* methamphetamine traces in the hair of the baby and an older sibling, which showed the children had been exposed to the toxic drug for at least six months; and
* two children, including one with special needs who required regular treatment, living in a P house.
Assistant Police Commissioner Malcolm Burgess said the number of children found in clan labs gave police serious concern, as the dangers and risks from being exposed to a clan lab were enormous - chemical poisoning, chemical burns, fires and explosions. Many of the combustible chemicals used in cooking P were fatal if swallowed.
Detective Inspector Chris Page, who led the month-long operation in the Waikato said the district-wide November sting indicated the number of children exposed to drugs and dealing continued to rise.
"It's not just the risk of fire, explosion or exposure to toxic and potentially carcinogenic chemicals that can put children at risk," he said.
"There is also the psychological ill-effects of being exposed to people involved in organised crime with its inherently destructive nature involving weapons and violence.
"The attitudes and values of these people are a far cry from what can be described as acceptable environments for children to live in."
Police recovered up to 10 grams of methamphetamine, more than $10,000 in cash, four firearms and two stun guns, $34,500 worth of stolen property including several laptops and a $20,000 car.
Older children were also found. At a house in Huntly police arrested a 16-year-old and two adults where Mr Page said the teenager had been exposed to a lifetime of drug dealing and crime.
"The disappointing thing was that essentially the child had been brought up in an environment where drug dealing was considered acceptable and the child's observations could essentially have been their apprenticeship.
"While we're very pleased to be able to catch and prosecute drug dealers it's tainted significantly by the finding of children in the condition they're in, in these houses."
It was the first time in his 27 years on the force Mr Page had encountered a mother breastfeeding while she was high.
Police arrested 22 people including 18 who were charged for Class A drug (methamphetamine) dealing and two for manufacturing.
