The chances of your second child dying of cot death after losing your first have been overestimated, according to a new study set to reignite the debate.
Cot death remains an unexplained phenomenon
Failure to hold a post-mortem, rule out murder or check for familial causes meant eight studies into the condition were defective, the UK research said.
The authors of the report, published in Archives of Disease in Childhood, hope to reassure those who had lost a child.
But implying that murder may sometimes be involved will prove controversial.
"It is likely there are some cases in which homicide is to blame," says Dr Christopher Bacon, the co-author of the report.
"But my main intention is to get the message across to those parents who have lost their first child that they do not have a significant risk of losing a second."
Dr Bacon looked at eight studies produced in English since 1970 which had reported relative risks of cot death recurring ranging from 1.7 to 10.1 times that of the general population.
The convictions of several mothers accused of murdering their young children have been overturned on appeal, mainly on the grounds that after losing one child to cot death there is a much higher chance of losing a second.
The prominent paediatrician Sir Roy Meadow was struck off by the General Medical Council after telling a court in the case of the late Sally Clark - accused of killing her two sons - that the chances of losing two children to cot death were 73m to one.
His figures were disputed by the Royal Statistical Society and other experts who said the odds of a second cot death were closer to 200 to one.
"Professor Meadow is one extreme," says Dr Bacon.
"But there are extremes at the other end too. Quite simply, there is no evidence to back up the 1 in 200 assertion. And it is extremely worrying for parents who have lost a child."
Dr Bacon is not the first to raise doubts about the figures. Last year, a report in the British Medical Journal raised similar questions about a Lancet study which concluded that almost 90% of second deaths in the same family are natural.
Professor Robert Carpenter stands by those figures.
Sir Roy was struck off by the GMC for his 'misleading evidence'
"It is important that parents do not live in fear that they will lose their second child too. But the 80-90% risk factor is based on very large samples.
"Dr Bacon wants the bar of suspicion to be much lower and I simply don't agree with that," he said, adding that he would prefer to see a guilty parent exonerated than an innocent one sent to prison.
Since 1991, the number of cot deaths has fallen by 75%, but seven babies still die this way every week in the UK. Reports of losing two children to cot death however remain very rare indeed.
The Foundation for the Study of Infant Deaths (FSID) said it welcomed all new research.
"This review will reassure bereaved parents that the chance of suffering a repeat sudden and unexplained death is low, especially in families where no major risk factors, such as a smoker in the household, are present.
"FSID stresses that it is very important that all infant deaths are investigated carefully and comprehensively."