During the study period, mothers of 21,987 children were exposed to the death of a relative during pregnancy, 14,206 were exposed to a relatives' serious illness during pregnancy and 7,331 of the offspring developed schizophrenia. The risk of schizophrenia and related disorders was approximately 67 percent greater among the offspring of women who were exposed to the death of a relative during the first trimester. However, death of a relative up to six months before or any other time during pregnancy was not related to risk for schizophrenia in the child, nor was exposure to serious illness in a relative. The association between a family death and risk of schizophrenia appeared to be significant only for individuals without a family history (parents, grandparents or siblings) of mental illness.

"Risk associated with exposure to a well - defined, objective stressful event confined to the first trimester of pregnancy suggests a number of possible mechanisms," the authors write. Chemicals released by the mother's brain in response to stress may have an effect on the fetus' developing brain. These effects may be strongest in early pregnancy, when protective barriers between the mother and fetus are not fully constructed.
(Arch Gen Psychiatry. 2008; 65[2]:146-152. Pre-embargo to the media at www.jamamedia.org.) van Available

Note: van Editor This study was funded by Tommy's the Baby Charity and the Stanley Medical Research Institute. Please see the article for additional information, including other authors, author contributions and affiliations, financial disclosures, funding and support, etc..