Nearly a quarter of Kiwi mothers continue to drink alcohol when they're pregnant, a new study has found.
The Ministry of Health's official advice is to abstain altogether - before conception right up until birth.
Researchers looked at data collected in the long-running Growing Up in New Zealand study. They found while 71 percent of women drank alcohol before becoming pregnant, 23 percent continued through the first trimester and 13 percent through the entire pregnancy.
Seven percent consumed four or more drinks a session during the first trimester - when the damage is worst - and 1 percent beyond that.
Up to 3000 children a year are born with foetal alcohol spectrum disorder (FASD), which leads to behavioural and intellectual problems, as well as heart defects and other health problems.
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Alcohol was much more likely to be consumed in the first trimester if the mother:
- didn't know she was pregnant
- was a teenager
- was living in the most deprived quintile
- was pregnant for the first time
- was Māori
- didn't plan to get pregnant.
From the second trimester onwards, young people were much more likely to stop drinking than mothers over 40.
Oddly, the study also found women who drank only small amounts - between one and three drinks a week - were more likely to keep consuming alcohol while pregnant than binge-drinkers. Thirty-eight percent of light drinkers kept up the habit during the first trimester and 27 percent kept drinking all the way through; while for binge drinkers, only 23 percent drank in the first few months, dropping to 3 percent from the second trimester.
A study in 2013 found only half of mothers were advised by their GP to stay off the booze while they were pregnant.
The latest study was published in the New Zealand Medical Journal. The Growing Up in New Zealand study has been following the lives of 7000 children and their parents since 2009.
'Too hard basket'
In an accompanying editorial, specialist Doug Sellman and alcohol researcher Jennie Connor said Kiwis appear to have been "brainwashed" into thinking alcohol was a "harmless recreational product which enhances quality of life".
"If there was a virus that produced devastating brain damage to the children of women who were infected during pregnancy, the rational response from health authorities and the government would be to take urgent steps to reduce the possibility of women contracting the virus; not just those who know they are pregnant, but all women of reproductive age," they wrote.
"What if it was a neurotoxin that could produce devastating brain damage to the children of women who ingested it during pregnancy, and it was known that consuming it during pregnancy was not a rare event but in fact occurred in a high proportion of unsuspecting pregnant women?
"If we knew up to 3,000 children were being needlessly brain-damaged every year in New Zealand because of exposure to this neurotoxin you would expect action of the highest priority by health authorities and the government to reduce this human misery and economic burden, using the best scientific evidence available."
In addition to FASD, the pair say alcohol has been linked to increased risks of stillbirth and cot death.
They're calling on the Government to implement the recommendations of the Law Commission's alcohol report of 2010.
"The John Key-led government of the time chose to enact a range of minor recommendations, while seeing off all of the major population-based interventions that have robust scientific evidence backing for their effectiveness in reducing alcohol-related harm."
Labour and the Greens, then in Opposition, said the reforms the Government eventually implemented had been watered down after lobbying from business interest groups such as the Food and Grocery Council and the Hospitality Association.
"It is not a shadow of the law the Law Commission would've," said then-Labour MP Lianne Dalziel.
Justice Minister Judith Collins said the changes struck a "sensible balance", saying people needed to willingly change their behaviour rather than have the law force them to do so.