Hazards of noise exposure on fetal hearing

Abstract

Many women of childbearing age are occupationally or recreationally exposed to hazardous levels of noise. Questions regarding the possibility of noise-induced hearing loss during fetal life have been posed. Advice to pregnant women regarding the safe limits of noise exposure has been lacking, because the evidence concerning the existence of fetal noise-induced hearing loss is sparse and the effects of intense noise exposures on the fetuses of pregnant women are largely unknown. Because of the nature of the fetal sound environment and the development of the ear, it is possible that fetal noise-induced hearing loss presents itself very differently than adult noise-induced hearing loss. Previous research in small mammals has suggested a critical period in development when susceptibility to noise exposure may be greater. Several investigations, using sheep as a model for in utero hearing loss, have provided evidence of fetal hearing changes after noise exposure. Although the reported epidemiological studies concerned with the possibility of fetal hearing loss had limitations, there were some suggestions of noise-induced hearing loss in children whose mothers experienced noise exposure. This article provides some background information concerning the possibility of fetal noise-induced hearing less.