SCHIZOPHRENIA AS A LONG-TERM OUTCOME OF PREGNANCY, DELIVERY, AND PERINATAL COMPLICATIONS - A 28-YEAR FOLLOW-UP OF THE 1966 NORTH FINLAND GENERAL-POPULATION BIRTH COHORT

Objective: The 1966 North Finland general population birth cohort was studied to determine whether abnormalities during pregnancy, delivery, and the neonatal period are associated with adult-onset schizophrenia , Method: The authors included all 11,017 subjects alive in Finland at age 16. For each individual, standardized assessments made during pre gnancy, delivery, and infancy were linked to national psychiatric case registers covering the period up to age 28. Subjects with DSM-III-R s chizophrenia were identified by using a two-stage screen that included perusal of individual case records. Associations (adjusted odds ratio s) between schizophrenia and specific pregnancy, delivery, and neonata l characteristics were calculated. Results: Within this cohort, 76 cas es of DSM-III-R schizophrenia arose by age 28 years; 51 (67.1%) of the se persons were men. Demographic characteristics and previous obstetri c histories of the mothers were similar in the case and unaffected com parison groups, although the former were more likely to have been move depressed than usual during pregnancy. Low birth weight (<2500 g) and the combination of low birth weight and short gestation (<37 weeks) w ere more common among the schizophrenic subjects. Being small for gest ational age (<10th percentile) was not more common. Of 125 survivors o f severe perinatal brain damage, six (4.8%) later developed schizophre nia. Conclusions: The spectrum of adverse outcomes after fetal and per inatal insults unfolded beyond childhood and included adult-onset schi zophrenia. The findings have implications for understanding the mechan isms involved in the development of schizophrenia and, possibly, for i ts prevention.