Dr Wilson told BBC News Online that while studies showed that families who lost one baby to cot death were at increased risk of a recurrence, it still was not entirely clear why this might be happening.
Mothers who registered the birth of the baby without a named father were six times more likely to lose the baby through a cot death than married couples.
Anne Diamond, the broadcaster who gave evidence to the Leveson inquiry about press intrusion following the cot death of her baby son, Sebastian, in 1991, said she felt "desperately hurt and disillusioned".