Hearing losses at 14 years of age were investigated in a questionnaire administered to 11,780 children born in Northern Finland in 1966 and followed up since pregnancy. Two samples of the whole material, one representing a sample of 413 children who reported impaired hearing and the other of 959 children who reported normal hearing, were calculated to represent a total material of 11,748 cases. Marked hearing loss, PTA greater than 25 dB in the better ear, was found in 64 children, minor loss, 4 kHz threshold greater than 20 dB in the better ear, in 420 children and slight abnormality, threshold greater than 20 dB at any frequency in 1,224 cases. Ear infections and also respiratory tract problems (asthma, sinusitis, upper respiratory tract infections etc.) which may be considered as risk factors for them were found to be significantly more predominant in pathological cases. In addition to the expected low frequency hearing losses, significantly more high tone losses were also found in the affected groups.