In 2012, the Ministry tore up a contract with the organisation that was trying to roll out the sleep pods because of safety fears that were never discussed with the founder, experts, academics or Coroners, the Herald found.
The Wahakura was designed more than a decade ago by Hastings GP Dr David Tipene-Leach, who was sickened by the unrelenting rate of Maori babies' accidental asphyxiation deaths.
New Zealand has the worst rate in the industrialised world for Sudden Unexpected Death in Infancy (SUDI), with Maori babies eight times more likely to die because they have higher chances of being exposed to smoke, bed-sharing with their parents and living in low-income households.
The portable pepi-pod, or wahakura, was designed to lie in the parent's bed, allowing Maori mothers the cultural custom of sleeping next to their babies, but decreasing the risk of death by giving the infant its own sleeping space.
When the Herald questioned why the Ministry had ignored repeated calls by experts and Coroners to fund the devices, officials argued there was no evidence-based research supporting their safety.
However, after the Herald's investigation was published Health Minister Jonathan Coleman overruled his officials and reversed the decade-long refusal to fund the pods, calling for an urgent national roll-out of the devices.
Yesterday, Otago University released the first evidence-based research proving wahakura are safe for infants.
Co-author of the research and wahakura founder, Tipene-Leach, said the study was a "major accomplishment''.
"These findings will give comfort to health workers who will be able to confidently promote a device that encourages a form of bed-sharing that increases safety for infants," he said.
The researchers recruited 200 predominantly Maori pregnant women from deprived areas of New Zealand and provided them with either a wahakura or bassinet and then compared the risks and benefits.
They asked the mothers to complete questionnaires about their baby's sleep patterns and used an infra-red video to record the baby's overnight sleep at one month old.
There was no evidence that using the wahakura increased the chance of adult-infant direct bed-sharing, which was a Ministry concern, but instead the study found the wahakura significantly increased the level of breastfeeding.
Professor Ed Mitchell, New Zealand's leading cot death expert, said the research was relevant not just to New Zealand, but to other countries which are also trialling the wahakura to reduce SUDI.
"There's a huge difference between asserting something is safe and being able to document it in a scientific way," he said.
"The findings are clear. It indicates that they're safe."