JERUSALEM — A new study published July 7, 2026, in the American Journal of Psychiatry reports that children born decades after World War II to mothers who were older than age five when Nazi persecutions began face an over two-fold increase in the risk of schizophrenia. The research indicates this elevated risk remained after adjusting for sociodemographic factors, birth weight, and the mother's history of psychiatric hospitalization.

The Hebrew University of Jerusalem's Braun School of Public Health and Community Medicine led the research. Professor Hagit Hochner and Dr. Iaroslav Youssim from the school directed the study. Professor Dolores Malaspina from Mount Sinai School of Medicine also co-led the research.

Researchers utilized data from the Jerusalem Perinatal Study, which tracked births in West Jerusalem between 1964 and 1976. They linked these records to Israel's National Psychiatric Registry through December 2004 to monitor hospitalizations for schizophrenia and related disorders. The team analyzed a data sample of 14,759 children of tracked mothers and 18,085 children of tracked fathers.

Parents were classified as 'exposed' if they were of Jewish ancestry, born in European countries under Nazi rule, and immigrated to Israel after anti-Jewish persecutions commenced in their home countries. Researchers further separated these exposed parents into subgroups based on whether they were five years old and younger, or older than five, when persecutions started. Unexposed parents were defined as those of European descent not living under Nazi rule.

No elevated risk of schizophrenia was detected in the offspring of parents who were five years old or younger when the persecutions began. While children of fathers who were older than five at the time of exposure initially showed an elevated risk of schizophrenia, this association became statistically non-significant after adjustment for sociodemographic variables.

"Our work underscores that war does not only have devastating immediate consequences, but also places a profound intergenerational burden on the future," said Professor Hochner, joint senior author of the study. She added, "As conflict and warfare continue to escalate and to displace and traumatize populations globally, understanding these preconception pathways is crucial for anticipating future public health burdens."