title: Prenatal ultrasound exposure and association with postnatal hearing outcomes.
abstract: OBJECTIVE
  Prenatal ultrasound exams have become increasingly frequent. Although no serious adverse effects are known, the public health implications would be enormous should adverse effects on auditory development be shown. This study looks to establish a possible correlation between hearing loss and increased prenatal ultrasound exposure.
  
  
  METHODS
  Retrospective cohort analysis.
  
  
  METHODS
  Tertiary academic referral center.
  
  
  METHODS
  A retrospective review of 100 children undergoing newborn hearing screening was conducted. Extensive data collection was performed, and this data was analyzed for a potential correlation between failure of newborn hearing screening and increased prenatal ultrasound exposure, as well as for a potential correlation of other variables with hearing loss.
  
  
  METHODS
  Postnatal hearing outcomes.
  
  
  RESULTS
  A higher number of both total and 3rd trimester ultrasound exams as well as a younger gestational age at birth were all found to be significantly associated with a higher likelihood of passing the newborn hearing screen (p<0.001 for each). No other factors were found to reach statistical significance.
  
  
  CONCLUSIONS
  Our results show that there is no correlation between a higher level of prenatal ultrasound exposure and hearing loss. Indeed, infants who had more prenatal ultrasounds in the third trimester were more likely to pass their screening hearing exams. The finding that children receiving more prenatal ultrasounds have a higher likelihood of passing newborn hearing screens serves as an excellent reminder of the classic statistics rule that correlation does not imply causation.
authors.affiliation: Department of Otolaryngology / Head and Neck Surgery, Georgia Regents University, 1120 15th Street, BP 4109, Augusta, GA 30912, USA. charbarger@gmail.com.
authors.forename: Claude F
authors.initials: CF
authors.lastname: Harbarger
authors.forename: Paul M
authors.initials: PM
authors.lastname: Weinberger
authors.forename: Jack C
authors.initials: JC
authors.lastname: Borders
authors.forename: Charles A
authors.initials: CA
authors.lastname: Hughes
mesh_terms: D005260:Female; D005865:Gestational Age; D034381:Hearing Loss / Q000453:epidemiology* / Q000209:etiology; D006801:Humans; D007231:Infant, Newborn; D015997:Neonatal Screening; D011247:Pregnancy; D011263:Pregnancy Trimester, Third; D012189:Retrospective Studies; D016216:Ultrasonography, Prenatal / Q000009:adverse effects / Q000706:statistics & numerical data