Does Preexisting Abnormality Cause Labor-Delivery Complications in Fetuses Who Will Develop Schizophrenia?
Many authors have suggested that theoretically the labor-delivery complications (LDCs) that frequently appear in the histories of individuals with schizophrenia represent the secondary consequence of preexistent abnormality in the fetus. The question of whether LDCs are systematically associated with prenatal complications and fetal abnormality was studied in 70 singleton schizophrenia patients, in 23 monozygotic twin pairs discordant and 10 pairs concordant for schizophrenia, and in 33 individuals with inferred genetic risk for schizophrenia. Schizophrenia cases with signs of prenatal abnormality (reduced head size, increased minor physical anomalies, greater within-twin-pair birthweight differences) did not have more LDCs than other schizophrenia cases. LDCs were not more frequent in genetic-risk cases with congenital malformations than in genetic-risk cases without malformations. Instead, individuals with schizophrenia who had a history of abnormal length of labor had significantly
