Prenatal smoke exposure was associated with hearing loss in a study of adolescents, which suggests that in utero exposure to tobacco smoke could be harmful to the auditory system, according to a study published Online First by JAMA Otolaryngology-Head & Neck Surgery.

Exposure to second-hand smoke (SHS) is a public health problem and exposure to tobacco smoke from in utero to adulthood is associated with a wide variety of health problems, the authors write in the study background.

Michael Weitzman, M.D., of the New York University School of Medicine, and colleagues studied data for 964 adolescents (ages 12 to 15 years) from the National Health and Nutrition Examination Survey 2005-2006 to determine whether exposure to prenatal tobacco smoke was associated with sensorineural hearing loss in adolescents.

Parents confirmed prenatal smoke exposure in about 16 percent of the 964 adolescents. Prenatal smoke exposure was associated with higher pure-tone hearing thresholds and an almost three-fold increase in the odds of unilateral low-frequency hearing loss, according to study results.

"The actual extent of hearing loss associated with prenatal smoke exposure in this study seems relatively modest; the largest difference in pure-tone hearing threshold between exposed and unexposed adolescents is less than 3 decibels, and most of the hearing loss is mild. However, an almost 3-fold increased odds of unilateral hearing loss in adolescents with prenatal smoke exposure is worrisome for many reasons," the study concludes.