Parents who lose a child less than a year old are at higher risk of an early death, according to UK research published Thursday.

Parents were more than twice as likely to die or become widowed in the first 15 years after the loss of a child less than a year old as those who not bereaved in this way, the study published in the British Medical Journal's Supportive and Palliative Care journal found.

Researchers looked at a random five percent sample of UK death registrations among parents whose child survived beyond the first year of life and those whose child died before reaching the age of one, between 1971 and 2006.

Bereaved mothers in England and Wales were found to be more than four times as likely to die in the first 15 years after losing a child than those who did not lose a child early.

Although the effects gradually lessened over time, bereaved mothers were still 1.5 times more likely to die up to 25 years after the death.

The authors said that they did not have sufficient data to rule out suicide but suggested that the stress of bereavement may leave a biological legacy, such as weakening the immune system.

Bereaved parents may also turn to damaging coping strategies such as alcohol abuse.