Effects on hearing during prolonged oral contraceptive use.

Different hearing defects have been attributed to prolonged use of oral contraceptives. The aim of the present investigation has been the evaluation by means of a number of audiological tests and of brain-stem evoked responses (BSER) of the possible incidence of subclinical pathology of the nervous hearing structures in these subjects. Twenty healthy subjects taking oral contraceptives from 9 to 30 months and 10 paired controls have been studied. No hearing loss was found but the study of BSER showed the presence of a significantly shorter latency of waves I and III which could be attributed to a functional alteration. Other, less significant, alterations are described and the conclusion is reached that prolonged oral contraception does not affect the hearing function, even if it is investigated with sophisticated techniques. However, the significant alterations of BSER responses and of the stapedial reflex might be considered as an initial non-organic sign of impairment of the central hearing pathways and therefore deserve further investigation.