Parents, and especially mothers, are at risk of hospitalization for mental illness after the death of a child, according to research released Wednesday.

For mothers, the risk of hospitalization was highest during the year following the child’s death, but stayed high for at least 5 years after the event.

Bereaved parents were most likely to be hospitalized for mental illness if they had no other children, Dr. Jiong Li of the University of Aarhus, Denmark and colleagues note in The New England Journal of Medicine.

“This suggests that having other children in the family may mitigate the effects of the loss of a child on a parent’s mental health,” they write.

Previous research has shown that parents often suffer from anxiety and depression after a child dies, and losing a child is more difficult than other types of bereavement.

During the current study, Li and colleagues followed 1,082,503 parents of children younger than 18 for almost 30 years, noting who lost a child and how they fared afterwards.

During the study period, 17,033 parents lost at least one child.

The investigators found that parents who lost a child were nearly 70 percent more likely to be hospitalized for any mental illness for the first time than parents who did not suffer the loss of a child. Bereaved mothers were more likely to check into a hospital for mental illness than bereaved fathers.

Mothers who lost at least 2 children had a more than three-fold higher chance of being hospitalized for a psychiatric disorder for the first time than mothers who didn’t lose any children. For fathers who lost at least 2 children, the risk of hospitalization increased by more than two-fold, relative to non-bereaved dads.

For mothers, the risk of hospitalization was highest in the year following the child’s death, and stayed higher than average for at least 5 years after the event.

The more additional children a woman had, the less likely she was to be hospitalized after one of them died.

Risk of hospitalization did not change with the age of the child or the bereaved parent.

SOURCE: The New England Journal of Medicine, March 24, 2005.