Prenatal exposure to maternal stress and subsequent schizophrenia. The May 1940 invasion of The Netherlands.
BACKGROUND
It has been suggested that prenatal exposure to maternal stress increases the risk of subsequently developing schizophrenia.


METHODS
The five-day invasion and defeat of The Netherlands by the German army in May 1940 constituted a severe, well-circumscribed national stressful event. Individuals exposed and non-exposed to this stressor in the first, second and third trimester of pregnancy were followed up for lifetime schizophrenia outcome through the National Psychiatric Case Register. REGISTER: Cumulative incidence of schizophrenia was higher in the exposed cohort (risk ratio (RR): 1.15, 95% CI 1.03-1.28), especially in those exposed in the first trimester (RR: 1.28, 95% CI 1.07-1.53). Significant interaction with gender was apparent in second trimester exposed cohorts (RR men: 1.35, 95% CI: 1.05-1.74; RR women: 0.83, 95% CI: 0.61-1.12).


CONCLUSIONS
Maternal stress during pregnancy may contribute to the development of vulnerability to schizophrenia. The apparent longer window of exposure in male foetuses may be related to the slower pace of male early cerebral development.
Department of Psychiatry and Neuropsychology, European Graduate School of Neuroscience, Maastricht University, The Netherlands.
J
J
van Os
J P
JP
Selten
D000328:Adult; D015331:Cohort Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008016:Life Change Events; D008297:Male; D018811:Maternal Exposure; D008875:Middle Aged; D009426:Netherlands / Q000453:epidemiology; D011247:Pregnancy; D011248:Pregnancy Complications / Q000453:epidemiology / Q000523:psychology; D011261:Pregnancy Trimester, First; D011262:Pregnancy Trimester, Second; D011263:Pregnancy Trimester, Third; D011297:Prenatal Exposure Delayed Effects; D012307:Risk Factors; D012559:Schizophrenia / Q000209:etiology*; D013315:Stress, Psychological / Q000453:epidemiology