THE death of a premature baby remains unexplained even after expert analysis, an inquest heard.

Miles Horwood was only two months old when he stopped breathing and suffered a cardiac arrest at his Bournemouth home, and the desperate efforts of his parents Craig and Susan, paramedics and emergency staff at Poole Hospital were to no avail. He died on November 11 last year.

He had only been home two weeks after spending more than a month in the trust's neonatal unit, having been born at 31 weeks and weighing only 895g, or two pounds.

During this period he had been feeding properly, growing and aside from a suspected upper respiratory tract infection identified on November 4 there was deemed to be no cause for concern.

An inquest at Bournemouth Coroner's Court heard a post mortem at London's specialist Great Ormond Street Hospital had found no specific explanation for his death.

Pathologist Liina Palm said Miles' death was likely in similar circumstances to Sudden Infant Death Syndrome, but didn't meet the strict criteria for that definition.

"A vulnerable baby, due to his birth-related problems, may be more prone to die suddenly in some situations where a healthy baby would have coped, such as a sudden drop in blood pressure or oxygenation for whatever reason," she said.

She gave the cause of death as "sudden unexplained death in infancy", noting that Miles was born prematurely and had suffered from complications during pregnancy.

There were no suspicious circumstances, the court heard.

Coroner Brendan Allen issued a verdict that Miles had died due to natural causes.