The failure of a cot’s structural integrity has been identified as the sole cause of a young baby’s tragic death after he became trapped between the mattress and a dislodged sliding side.

A coroner’s decision released today has found the accidental death of the 7-month-old baby – who cannot be identified – was caused by circumstances the parents were unlikely to have been aware of.

The baby had been growing well and lived in a healthy home environment with his own cot in his own room.

After a family dinner out, he was placed into his cot for the night at around 8pm, wrapped in his usual muslin cloth.

The decision said there was nothing unusual about the evening and it was normal for the baby to sleep through the night.

However, when his mother checked on him at around 7.20am, he was found stuck upright between the mattress and the bottom cache of the sliding rail had come out of its track. The top cache and sliding rail was still attached.

Unresponsive, an ambulance was called. The ambulance staff believed the mattress protector had tightened around the baby’s neck.

The baby was rushed to hospital but tragically passed away later that day.

He was found to have died from hypoxic brain injury and asphyxia due to a misplaced sliding side of the cot.

Coroner Seung Youn acknowledged the immense grief of the parents and said the circumstances of his death fell well outside any general advice of safe sleeping practices.

“I am satisfied [suppressed] death was a tragic accident.

“The evidence before me supports the conclusion that (the baby’s) mother was aware of and followed general safe-sleeping practices.

“It was the misplaced sliding side of (his) cot that created a gap and caused (him) to be trapped. I recognise that (his) mother was unlikely to have been aware of the misplaced sliding side that caused a gap between the side of the cot and mattress,” Coroner Youn said.

The coroner said although the Ministry of Health has published guidelines around safe sleeping, messaging around the structural integrity of cots should be included.

“In order to emphasise that a small gap between the side of the bed and mattress caused by misplaced sliding sides can increase risk of fatality, the message of safe sleeping practices should always include the message that the structural integrity of cots should be regularly checked to ensure no gaps can be created between the bed sides and mattress,” the coroner said.

The Ministry of Health acknowledged this was not included in their messaging but has recommended it be added in their latest review.

Plunket New Zealand told the coroner the organisation has since strengthened its messaging online and in resources provided to families around checking the structure of cots.

Hāpai te Hauora, the national sudden unexpected death in infancy (SUDI) co-ordination service, also told the coroner the organisation support the recommendation and are currently preparing revised messaging in their training packages and education sessions.

“I take this opportunity to extend my sincere condolences to the whānau of baby [suppressed] for their loss,” the coroner concluded.