The role of prenatal stress as a pathway to personality disorder: longitudinal birth cohort study.

BACKGROUND: Many studies have reported associations between prenatal stress and the development of psychotic, anxiety and depressive disorders; however, to date no studies have investigated potential associations with personality disorders. AIMS: This study investigated potential associations between exposure to prenatal stress and personality disorder in offspring. METHOD: In a subsample (N = 3626) of a large Finnish birth cohort, we used logistic regression models to examine associations between self-reported maternal stress during pregnancy, collected monthly during antenatal clinic appointments, and personality disorder in offspring. Familial and outcome information were obtained by linking data from the Finnish Hospital Discharge Register and the Finnish Population Register. RESULTS: Compared with those unexposed, children exposed to any maternal stress during gestation had three times the odds of developing a personality disorder (odds ratio 2.76, 95% CI 1.59-4.80, P = 0.000). Those exposed to moderate stress had three times the odds (odds ratio 3.13, 95% CI 1.42-6.88, P = 0.005) and those exposed to severe stress had seven times the odds (odds ratio 7.06, 95% CI 2.10-23.81, P = 0.002) of developing a personality disorder. These associations remained after adjusting for parental psychiatric history, comorbid psychiatric diagnoses, prenatal smoking and antenatal depression. CONCLUSIONS: Exposure to stress during gestation increases the odds of personality disorder in offspring, independent of other psychiatric disorders. These results suggest the assessment of maternal stress and well-being during pregnancy may be useful in identifying those at greatest risk of developing personality disorder, and highlight the importance of prenatal care for good maternal mental health during pregnancy.