Sensorineural hearing of 359 otoscopically and tympanometrically normal 5-year-old children with known otitis-history was studied under ideal conditions. In the subgroups of children with a different number (0, 1-2, 3-7, greater than or equal to 8) of attacks of acute otitis media (AOM) in their history, the mean bone conduction thresholds unregularly varied from 0.1 dB to 7.4 dB, depending on the frequency and the subgroup studied. The proportion of the ears with a bone conduction threshold greater than 10 dB at 0.5, 1, 2 or kHz ranged, also unregularly, from 10.8% to 0.5%, the greatest percentages being found at 0.5 and 1 kHz in the children without a history of AOM. Thus, neither AOM nor its treatment, even if frequently occurring, seem to cause permanent sensorineural hearing loss in children.