Maternal infections and subsequent psychosis among offspring

Background: We tested the hypothesis that maternal infections during pregna ncy are associated with the subs equent development of schizophrenia and ot her psychoses in adulthood. Methods: We conducted a nested case-control study of 27 adults with schizop hrenia and other psychotic illnesses and 54 matched unaffected control subj ects (matched for sex, ethnicity, and date of birth) from the Providence, R I, cohort of the Collaborative Perinatal Project. We retrieved stored blood samples that had been obtained from these mothers at the end of pregnancy. These samples were analyzed for total class-specific immunoglobulins and f or specific antibodies directed at recognized perinatal pathogens capable o f affecting brain development. Results: Maternal levels of IgG and IgM class immunoglobulins before the mo thers were delivered of their neonates were significantly elevated among th e case series (t=3.06, P=.003; t=2.93, P=.004, respectively, for IgG and Ig M immunoglobulin-albumin ratios). Secondary analyses indicated a significan t association between maternal antibodies to herpes simplex virus type 2 gl ycoprotein gG2 and subsequent psychotic illness (matched t test=2.43, P=.02 ). We didn't find significant differences between case and control mothers in the serum levels of IgA class immunoglobulins, or in specific IgG antibo dies to herpes simplex Virus type 1, cytomegalovirus, Toxoplasma gondii, ru bella virus, human parvovirus B19, Chlamydia trachomatis, or human papillom avirus type 16. Conclusions: The offspring of mothers with elevated levels of total IgG and IgM immunoglobulins and antibodies to herpes simplex virus type 2 are at i ncreased risk for the development of schizophrenia and other psychotic illn esses in adulthood.