The present material is based on a birth cohort of 2,512 children followed up from the antenatal period. Data on middle ear infections were collected until the children were 7 years. At the age of 7, audiometry was performed on 298 of them. For reasons other than middle ear infection, 32 children were excluded and the final material comprised 266 children. Only those children with clear differences in their history for otitis media were analysed. Although the pure tone averages (0.5-3 kHz) showed no major changes, different mean air-conduction (AC) thresholds were associated with different histories of otitis media. The 35 healthy children (with no otitis media episodes until 2 years of age) showed the best mean AC thresholds. The 51 children with recurrent acute otitis media (RAOM; > or = 4 episodes of acute otitis media) showed worse thresholds at the high frequencies and those 13 who had had secretory otitis media (SOM) at all frequencies. The children with a history of otitis media, either RAOM or SOM, more often had hearing thresholds exceeding 20 dB. Our results might indicate inner ear involvement in these long-term follow-up hearing thresholds.