title: Comparison of maturational process of hearing threshold in early life between at-risk and low-risk preterm infants.
abstract: To detect any abnormality in the maturational process of hearing threshold during the early life in at-risk preterm infants.
  
  
  
  The threshold of brainstem auditory evoked response was recorded and analyzed longitudinally from 30 to 42weeks of postconceptional age in 357 at-risk infants born at 23-36weeks of gestation. The results were compared with those in 82 low-risk infants born at 30-42weeks at various postconceptional ages.
  
  
  
  From 31 to 42weeks, the response threshold in the at-risk infants was consistently slightly higher than that in the low-risk infants. No statistically significant difference was found between the two groups of infants at any designated postconceptional ages. The threshold in the at-risk infants born at 23-29weeks of gestation tended to be higher than those born at 30-36weeks at various postconceptional ages, but the difference did not reach statistical significance. There was also no significant difference in the slope of BAER threshold-age function between the at-risk infants, irrespective of gestational ages, and the low-risk infants.
  
  
  
  During the early life, hearing threshold in at-risk preterm, mainly very preterm, infants is marginally elevated, but the maturational process of the threshold is generally similar to that in low-risk infants, without notable abnormality.
authors.affiliation: Division of Neonatology, Children's Hospital, Fudan University, Shanghai, China. Electronic address: jiangzedong-oxshang@hotmail.com.
authors.forename: Ze D
authors.initials: ZD
authors.lastname: Jiang
authors.affiliation: Department of ENT, Children's Hospital, Fudan University, Shanghai, China.
authors.forename: Zheng M
authors.initials: ZM
authors.lastname: Xu
authors.affiliation: Neonatal Unit, Department of Paediatrics, John Radcliffe Hospital, University of Oxford, Oxford, United Kingdom.
authors.forename: Andrew R
authors.initials: AR
authors.lastname: Wilkinson
mesh_terms: D016022:Case-Control Studies; D016057:Evoked Potentials, Auditory, Brain Stem; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D007234:Infant, Premature / Q000254:growth & development / Q000502:physiology*; D008297:Male; D012684:Sensory Thresholds
keywords: Brainstem auditory evoked response; Hearing impairment; Neonatal hearing screening; Preterm birth