Summary: A new study demonstrated that women who endured Nazi persecution as young girls passed a significantly elevated risk of psychiatric illness to their children born decades after World War II. Specifically, children born to mothers who were older than age five when the persecutions began face a stark, over two-fold increase in the risk of developing schizophrenia.
Key Facts
The Two-Fold Schizophrenia Spike: The study’s core finding revealed that offspring born to mothers who were older than five years old at the initiation of Nazi persecution suffered a 2-fold increase in schizophrenia risk. This metric remained highly robust even after researchers rigorously adjusted for birth weight, sociodemographic factors, and the mothers’ own history of psychiatric hospitalization.
The Five-Year Shield Effect: Strikingly, no elevated risk of schizophrenia was found in children whose parents were five years old or younger when the persecutions began. Researchers hypothesize that these toddlers were either tightly shielded from the environmental horrors by primary caregivers, or their early cognitive faculties altered their long-term perception of ambient danger.
Maternal vs. Paternal Disconnect: The study unmasked a powerful difference in how trauma travels through family lines. While the children of heavily traumatized fathers initially displayed a slight elevation in psychiatric vulnerability, this connection vanished completely and became statistically non-significant once sociodemographic variables were adjusted.
The Intrauterine & Germline Hypothesis: The absolute persistence of the maternal line indicates that preconception trauma in girls alters future generations through highly distinct biological pathways. The researchers emphasize that early-life trauma may leave a permanent imprint via epigenetic modifications in the maternal germline (the cellular lineage that forms future eggs) or by fundamentally altering the maternal intrauterine environment during future pregnancies.
A Public Health Warning for Modern Warfare: Senior author Hagit Hochner notes that as conflicts and global displacement continue to escalate across the world, these findings are a vital warning. Warfare does not merely inflict immediate casualties; it fundamentally shapes the public health burden of generations born decades into the future.
Source: Hebrew University of Jerusalem
Children born decades after World War II to mothers who were older than age 5 at the time of the initiation of Nazi persecutions, face and over two-fold increase in the risk of schizophrenia, according to a study published in the American Journal of Psychiatry.
The research was led by Prof. Hagit Hochner and Dr. Iaroslav Youssim from the Braun School of Public Health and Community Medicine at the Hebrew University of Jerusalem and Prof. Dolores Malaspina from Mount Sinai School of Medicine, New York, and their colleagues. The research team investigated the long-term, intergenerational impacts of severe preconception trauma by evaluating whether the children of Holocaust survivors are at increased risk for severe psychiatric disorders.
Tracking Two Generations of Health Data
To understand this relationship, 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 two large data samples consisting 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. The researchers further separated these parents into subgroups based on how old they were when the persecutions began: either five years old and younger, or older than five. Unexposed parents were of European descent not living under Nazi rule.
The Crucial Factor of Age and Timing
The findings revealed a stark difference based on the parent’s age at the time of the trauma. Offspring of mothers who were older than age five when Nazi persecutions began demonstrated an over two-fold increase in the risk of schizophrenia. This risk remained highly pronounced and statistically robust even after the researchers adjusted for sociodemographic factors, birth weight, and the mother’s own history of psychiatric hospitalization.
Conversely, no elevated risk of schizophrenia was detected in the offspring of parents who were five years old or younger when the persecutions started. The researchers suggested that very young children might have been better shielded from their immediate environment by primary caregivers, or that their developing cognitive faculties altered their perception of the danger around them.
Maternal vs. Paternal Inheritance Pathways
The study also illuminated notable differences between maternal and paternal trauma transmission. While the children of fathers who were older than five at the time of exposure initially showed an elevated risk of schizophrenia, this association diminished and became statistically non-significant once adjusted for sociodemographic variables.
The enduring strength of the maternal connection suggests that the intergenerational transmission of trauma may operate through distinct biological and environmental pathways. The researchers noted that maternal trauma might impact future generations via the intrauterine environment during pregnancy, greater maternal engagement in early childhood parenting, or epigenetic alterations in the germline that transmit stress information across generations.
While the study had limitations, such as an inability to capture subjective personal experiences of the Holocaust or tracking participants past 2005 when later-onset cases might appear, its population-based design provides substantial evidence of how historical atrocities leave an imprint on the mental health of subsequent generations. Professor Hochner and her team emphasized that ongoing research across different historical and geographical settings will remain vital to fully understand the deep-rooted legacies of trauma.
“Our work underscores that war does not only have devastating immediate consequences, but also places a profound intergenerational burden on the future,” said Prof. Hagit Hochner, joint senior author of the study.
“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. It is in fact our professional duty to study these effects and to bring it to public awareness. Ending war and striving for peace is a Public Health imperative.”
Key Questions Answered:
Editorial Notes:
This article was edited by a Neuroscience News editor.
Journal paper reviewed in full.
Additional context added by our staff.
About this schizophrenia and epigenetics research news
Author: Danae Marx
Source: Hebrew University of Jerusalem
Contact: Danae Marx – Hebrew University of Jerusalem
Image: The image is credited to Neuroscience News
Original Research: Open access.
“Schizophrenia in Offspring of Holocaust Survivors: Intergenerational Effects of Preconception Parental Trauma Within the Jerusalem Perinatal Study” by David S. Siscovick, Dolores Malaspina, Hagit Hochner, Iaroslav Youssim, Ilona Shapiro, Ora Paltiel, Orly Manor, Ronit Calderon-Margalit, Salomon Israel, Yechiel Friedlander. American Journal of Psychiatry
DOI:10.1176/appi.ajp.20241145
Abstract
Schizophrenia in Offspring of Holocaust Survivors: Intergenerational Effects of Preconception Parental Trauma Within the Jerusalem Perinatal Study
Objective:
The role of parental preconception trauma in the pathogenesis of psychiatric disorders remains unclear. The authors investigated whether offspring of Holocaust survivors, born years later, are at increased risk of schizophrenia.
Methods:
Data from the Jerusalem Perinatal Study (1964–1976) were linked to Israel’s National Psychiatric Registry. Parents from European countries under Nazi rule who immigrated to Israel after the anti-Jewish persecutions began were classified as exposed. Parents were further categorized by their own age (≤5 or >5 years) when the persecutions began. Unexposed parents were of European descent not living under Nazi rule. Two offspring subsamples were assembled: 14,759 offspring of 7,316 mothers and 18,085 offspring of 8,833 fathers, of whom 3,913 had exposed mothers and 5,672 had exposed fathers. For each offspring subsample, Cox models were used to analyze time to first schizophrenia hospitalization.
Results:
In minimally adjusted models, offspring of parents who were older than age 5 at exposure showed elevated schizophrenia rates (maternal exposure: hazard ratio=2.71, 95% CI=1.60–4.61; paternal exposure: hazard ratio=1.52, 95% CI=1.01–2.28). No associations were observed in offspring whose parents were exposed earlier (≤5 years). Adjustments for sociodemographic variables diminished the association of paternal exposure at age >5, whereas association with maternal exposure remained strong (hazard ratio=2.38, 95% CI=1.20–4.70) and withstood further adjustments for mother’s psychiatric hospitalization (hazard ratio=3.73, 95% CI=1.87–7.43) and other covariates.
Conclusions:
Offspring of mothers who were older than age 5 when Nazi persecutions began showed over a twofold increase in schizophrenia risk, underscoring the potential impact of trauma and its timing during the preconception period in the pathogenesis of schizophrenia.
Source: Neuroscience News
