Severe Maternal Stress Linked to Schizophrenia in Children
Pregnant women exposed to high stress situations are more likely to have children who go on to develop schizophrenia. Stress of the type endured during natural disasters such as hurricanes or earthquakes is as devastating as that experienced in a war zone, according to the latest research.
Professor Delores Malaspina, of New York University School of Medicine and colleagues, reviewed data from over 88,000 medical records of people born in Jerusalem between 1964 and 1976. Children of women who were in their second month of pregnancy at the height of the Arab-Israeli war in 1967, were found to be more likely to develop schizophrenia in later life. Men were found to be 1.2 times more likely to develop schizophrenia, whilst women were 4.3 times more likely.
The study, published on the open-access journal BMC Psychiatry Research, supports a growing body of evidence that suggests maternal exposure to high stress situations increases the vulnerability of offspring to psychological problems later in life. The second month of pregnancy appears to be a particularly sensitive period in fetal development. "The placenta is very sensitive to stress hormones in the mother. These hormones were probably amplified during the time of war," said Malaspina.
Are females more vulnerable to schizophrenia if the mother is exposed to high levels of stress? Despite the higher numbers Malaspina suspects this is not the case. A more likely reason, she suggests, is that more male babies died so were never available for subsequent study. "Many studies have shown a change in the sex ratio of a population undergoing severe upheaval or stress, and that change is a loss of male fetuses," she says.
Mothers should not be concerned by the stresses and strains of everyday life. Stress is both normal and natural and, according to Malaspina, the fetus may actually benefit from some exposure to stress hormones in order to normalize their own stress functioning.
BMC Psychiatry DOI: 10.1186/1471-244X-8-71