Fortunately, schizophrenia remains uncommon even though it is a serious, long-term mental disorder that disrupts thinking, emotions, and perception of reality through symptoms such as hallucinations, delusions, disorganized thoughts, and reduced motivation.

The condition, increasingly viewed as neurodevelopmental, impacts roughly 25 million individuals globally and about 70,000 people in Israel, or one in 143 residents.

Adult offspring of Holocaust survivors frequently carry trauma from childhood exposure to their parents' accounts of suffering or from the silence surrounding those events.

A recent study from the Hebrew University of Jerusalem shows that individuals born years after the Holocaust to parents who were over age five when Nazi persecution began carry a higher risk of schizophrenia, indicating that parental trauma can shape the mental health of children born decades afterward.

This pattern of preconception influence highlights how intense childhood trauma in one generation can quietly shape psychiatric outcomes in the next, pointing to particular windows of childhood vulnerability.

The project was directed by Prof. Hagit Hochner and Dr. Iaroslav Youssim of the Braun School of Public Health along with Prof. Dolores Malaspina of Mount Sinai and additional colleagues from Hebrew University.

Offspring of mothers older than five at the start of Nazi persecution showed more than double the risk of schizophrenia, according to findings published in the American Journal of Psychiatry under the title Schizophrenia in Offspring of Holocaust Survivors.

Researchers examined intergenerational effects using records from the Jerusalem Perinatal Study covering births in West Jerusalem from 1964 to 1976, which were then connected to Israel's National Psychiatric Registry through 2004.

Two large cohorts were analyzed: 14,759 children of tracked mothers and 18,085 children of tracked fathers.

Parents were labeled exposed if they were Jewish, born in Nazi-occupied European countries, and arrived in Israel after persecution started; they were further grouped by age at onset of persecution, either five or younger or older than five.

Children of mothers older than five at the time of exposure retained a clear, statistically significant increase in risk after adjustments for social and demographic factors, birth weight, and maternal psychiatric history.

No similar elevation appeared among offspring of parents who were five or younger when persecution began, possibly because very young children were more protected by caregivers or perceived danger differently.

Prof. Hochner noted that conflict carries lasting intergenerational consequences beyond immediate destruction and stressed the need for peace efforts amid rising global conflicts.

Paternal vs maternal

Initial findings suggested elevated risk from exposed fathers, yet this association weakened and lost significance after sociodemographic adjustments, while the maternal link remained robust.

Maternal trauma may transmit effects through prenatal environment, early parenting interactions, or epigenetic mechanisms affecting stress responses across generations.

Hochner emphasized that the results indicate increased risk rather than certainty, noting that schizophrenia is uncommon and most children of survivors remain unaffected.

Interest in the work has extended to other post-conflict regions, with inquiries from Bosnia and potential relevance to populations affected by conflicts in Rwanda, Syria, Ukraine, and elsewhere.

The observational design identifies associations but cannot establish causation or biological pathways, and the study did not explore prevention strategies or third-generation outcomes.

Despite limits such as the inability to measure personal Holocaust experiences or follow participants beyond 2005, the population-based approach offers strong evidence of lasting mental-health effects across generations.

Further studies in varied settings will help clarify these legacies, Hochner said, while underscoring the resilience shown by survivors who rebuilt families and careers.