The relationship between long-lasting, bilateral otitis media with effusion (OME) between the ages of 2 and 4 and educational attainment, in particular, reading and spelling ability at 7 years of age, was studied in a prospective cohort study of 946 children. After selection, three groups were distinguished: 151 children with long-lasting, bilateral OME at preschool age, 37 preschool children treated with ventilation tubes, and 82 children with no history of OME at that age. Early bilateral OME was found to affect spelling ability, but not reading ability, at 7 years. The effects of OME did not appear to increase with the number of observations of OME. Also, recurrent hearing loss did not have more detrimental effects than continuous hearing loss. Effects of treatment with ventilation tubes were not found. Only the teachers' ratings of writing ability indicated a slight advantage of treatment with ventilation tubes. In conclusion, the educational consequences of early OME appear to be very small.