Israeli Study Links Maternal Holocaust Trauma to Higher Schizophrenia Risk in Children

A new study by researchers from the Hebrew University of Jerusalem suggests that the psychological impact of the Holocaust may extend across generations. The findings indicate that children of female Holocaust survivors who were older than five years of age when Nazi persecution began have a significantly higher risk of developing schizophrenia later in life.

The research, published in the American Journal of Psychiatry, analyzed data from the Jerusalem Perinatal Study, which followed more than 32,000 children born in Jerusalem between 1964 and 1976. Scientists examined records of 14,759 children born to 7,316 Holocaust survivor mothers and 18,085 children born to 8,833 Holocaust survivor fathers, tracking their mental health outcomes for more than three decades through Israel's national psychiatric registry.

Parents were classified as Holocaust survivors if they were Jewish, born in European countries occupied by Nazi Germany, and emigrated after persecution had begun. Researchers divided them into two groups depending on whether they had been five years old or younger, or older than five, when the persecution started. A comparison group consisted of Jewish parents of European origin who had not lived under Nazi rule.

The study found that children whose mothers had been older than five at the onset of Nazi persecution were 2.38 times more likely to develop schizophrenia than children whose mothers had not experienced the Holocaust. No similar increase in risk was observed among children whose mothers had been five years old or younger when the persecution began. Likewise, researchers found no significant association between paternal Holocaust exposure and schizophrenia risk in offspring.

The incidence of schizophrenia reached seven cases per 10,000 person-years among children of mothers exposed after age five, compared with 2.7 cases per 10,000 person-years in the control group. Other factors linked to a higher risk included a maternal history of psychiatric hospitalization and low birth weight.

According to the researchers, the findings do not prove that maternal trauma directly causes schizophrenia in the next generation. However, they suggest several possible biological mechanisms, including epigenetic changes that influence gene activity without altering DNA, as well as trauma-related effects on the maternal immune system, microbiome and the prenatal environment.

The authors note that previous studies have connected Holocaust-related trauma with increased risks of post-traumatic stress disorder, anxiety, depression and other mental health problems in descendants of survivors, while evidence regarding schizophrenia has remained inconsistent. They say the new findings highlight the need for further research into how severe trauma experienced before conception may influence the health of future generations.

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