Research published in the open access journal BMC Psychiatry supports a
growing body of literature that attributes maternal exposure to severe
stress during the early months of pregnancy to an increased
susceptibility to schizophrenia in the offspring.
According
to lead author Dolores Malaspina M.D., M.Sc.P.H., Anita Steckler and
Joseph Steckler Professor of Psychiatry at the NYU School of Medicine.
"The stresses in question are those that would be experienced in a
natural disaster such as an earthquake or hurricane, a terrorist
attack, or a sudden bereavement".
Data from 88,829 people,
born in Jerusalem from 1964 to 1976, were collected from the Jerusalem
Perinatal Study that linked birth records to Israel's Psychiatric
Registry. The authors discovered that the offspring of women who
were in their second month of pregnancy during the height of the
Arab-Israeli war in June of 1967 (the "Six Day War") displayed a
significantly higher incidence of schizophrenia over the following
21-33 years. The study also showed that the pattern was
gender-specific, affecting females more than males.
Following
the 1967 war, females who had been in their second month of fetal life
during the conflict were 4.3 times more likely to develop schizophrenia
than females born at other times. Males in their second month of fetal
life were 1.2 times more likely to develop schizophrenia. "It's a very
striking confirmation of something that has been suspected for quite
some time", said Malaspina.
"The placenta is very sensitive
to stress hormones in the mother," explains Malaspina, "these hormones
were probably amplified during the time of the war."
The
authors point out that the study, which assessed ongoing medical
records, only supports, rather than proves, the hypothesis that the
greatest vulnerability to schizophrenia is in the second month of
pregnancy. Limitations to the study include a small sample population
as well as the absence of information on the exact length of gestation,
which makes it possible that developmental stages were underestimated.
Malaspina also points out that pregnant women in general should not be alarmed about handling daily stressors during pregnancy. "A developing fetus requires some exposure to maternal stress hormones as it normalizes their stress functioning," she says. "But women experiencing anxiety or excessive stress would do well to address it before a planned pregnancy and to have good social support systems."
Source: Adapted from materials provided by EurekAlert (Press Release)
