Stress during pregnancy is linked to miscarriage, psychiatrists have found. Pregnant women who experience severe life events, such as the death of someone very close, the loss of a job or finding that their partner has been unfaithful, are more likely to miscarry.
Forty-eight women who had miscarried were matched with 48 who had not. Each couple was matched for known predictors of miscarriage.
The authors of a report in this month's British Journal of Psychiatry found that 54 per cent of the miscarriage group had experienced social stress during the three months preceding miscarriage or an emotional shock in the fortnight beforehand. Only 15 per cent of the control group had experienced such stress.
Tom O'Hare, consultant psychiatrist at Birch Hill hospital in Rochdale, who did the study with Francis Creed of the University of Manchester, agreed that folk wisdom has predicted that stress might cause miscarriage.
It is common knowledge, for example that sheep-worrying can cause spontaneous abortion in ewes. "It has always been a bit controversial in humans," he said. "There has not been any hard evidence. Possibly we have always looked for physical causes, stress has been difficult to measure, and studies are often flawed."
The authors only found a link between miscarriage and severe life events. Other life events, such as moving house, getting married or even the death of a grandparent, were not predictors.
It is also possible that there is a factor that predisposes women to both stress and miscarriage. This could be a personality trait or something in the environment.
The authors found, for example, that if a woman had been separated from her own mother during her childhood this increased her chances of miscarriage.
"This explanation is not incompatible with the stress hypothesis and it could be that all these elements interact in a complex way along with genetic and immunological determinants," they said.