One of the county's leading baby specialists says more mothers are smoking methamphetamine during pregnancy.
Paediatrician Dr Simon Rowley estimates between one and two babies are born each week at Starship Hospital having been exposed to meth in the womb.
There is currently an epidemic of babies being born with effects of methamphetamine.
Dr Rowley says the mothers he sees are often all over the place.
"Instead of having a regular timetable of sleeping, waking and feeding and being alert, they're just generally disorganised and all over the place, often very jittery."
Dr Rowley says he often works with mothers as young as 17 who have in some cases been smoking, drinking and doing P during pregnancy. He sees up to two babies born each week affected by meth.
"It's a bit of a vicious cycle really because they are extremely vulnerable in that situation," he says.
Some situations are so dire that in certain cases new-borns have to be weaned off the drug using morphine.
More than 100 Kiwi babies are involved in a world-first study tracking the long-term impacts of prenatal exposure to meth. Thirteen years in, those impacts are still notable.
Development psychologist Dr Trecia Wouldes says the worst effects are seen in boys.
"The first study we did looking at motor development and cognitive development showed there was a delay in motor development across the board. There wasn't a delay in cognitive development except for with the boys."
"What we really need is an early intervention programme where we identify these women during pregnancy," says Dr Rowley. "They want to have a baby that's healthy, so we get involved."
Research into the impact of the drug is still very much in its own stages of infancy.