Comparative Study of Hearing Impairment among Healthy and Intensive Care unit Neonates in Mashhad, North East Iran

Document Type: Original


1 Neonatal Research Center, Imam Reza Hospital, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran.

2 Sinus and Surgical Endoscopic Research Center, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran.

3 3Department of Pediatrics, Ghaem Hospital, Mashhad University of Medical Sciences, Mashhad, Iran.

4 Audiologist, Member of Khorasan Cochlear Implant, Mashhad, Iran.

5 Medical Student(Intern), Department of Pediatrics, Imam Reza Hospital, Mashhad University of Medical Sciences, Mashhad, Iran.


According to World Health Organization (WHO) 2001 statistics, hearing disorders are the most common congenital disease, and the incidence rate among high-risk newborns is as much as ten times as high as that in healthy neonates. However, 78% of screening test failures are well-baby nursery babies. The Joint Committee on Infants’ Hearing (JCIH) has emphasized the importance of early diagnosis and treatment in neonates with hearing impairments in order to preserve their maximum linguistic skills. The aim of our study was to compare the prevalence of hearing loss among babies in the neonatal intensive care unit (NICU) and the rooming-in unit (RIU), and study their risk factors.
Materials and Methods:
Neonates born in three hospitals in Mashhad between 2008 to 2010 were studied prospectively and screened for auditory disorders using the oto acoustic emission (OAE) test at the time of discharge and 3 weeks later. To confirm hearing loss, the auditory steady state response (ASSR) test was used among those participants who failed both OAE tests.
Two-thousand and sixty-three neonates from the NICU were screened and compared with a control group consisting of 8,724 neonates from the RIU or the well-baby nursery. At the end of the study, hearing impairment as confirmed by failure in the ASSR test was diagnosed in 31 neonates (26 in the control group [0.30%] and five in the NICU group [1.94%]).
In our study, the prevalence of hearing disorders among NICU neonates was 6.5-times greater than that among babies from the RIU or well-baby unit. This observation demonstrates the importance of universal screening programs particularly for high-risk population neonates.


1. Parving A. Prevalence of congenital hearing impairment and risk factors. Neonatal hearing screening. In: Grandori F, Lutman M. The European Consensus Development Conference on Neonatal Hearing Screening. Milan: 1998; pp: 6–10.

2. Moeller MP. Early intervention and language development in children who are deaf and hard of hearing. Pediatrics. 2000; 106(3):43–51.

3. Hayes D. Newborn hearing screening: selected experience in the United States. Scand Audiol. 2001; 30(53):29–32.

4. Yoshinaga-Itano C, Sedey AL, Coulter BA, Mehi AL. Language of early and later-identified children with hearing loss. Pediatrics. 1998; 102(5):1168–71.

5. Apuzzo ML, Yoshinaga-Itano C. Early identification of infants with significant hearing loss and the Minnesota Child Development Inventory. Semin Hear. 1995; 16:124–39.

6. Behrman R, Kliegman R, Jonson H (Ed s) Nelson Text book of Pediatrics. 16th ed. 2000: 1940-46.

7.  Korres SNikolopoulos TPKomkotou V,  Balatsouras D, Kandiloros D, Constantinou D. Newborn hearing screening: effectiveness, importance of high-risk factors, and characteristics of infants in the neonatal intensive care unit and well-baby nursery. Otol Neurotol . 2005; 26(6): 1186–90.

8. American Speech-Language-Hearing Association. (2007). Executive Summary for JCIH Year 2007 Position Statement: Principles and Guidelines for Early Hearing Detection and Intervention Programs. Available from www. asha. org.

9.  Nafstad P, Samuelsen SO, Irgens LM, Bjerkedal T. Birth weight and hearing impairment in Norwegians born from 1967 to 1993. Pediatrics. 2002; 110(3):30.

10. Wilcox AJ, Russell IT. Birth weight and prenatal mortality: I. on the frequency distribution of birth weight: Int J Epidemiology. 1983; 12:314–8.

11. Morant A, Pitach M, Garcia F. The delay of the diagnosis of deafness in children. An Esp Pediatr. 1999; 51(1); 49–52.

12. Vohr BR, Widen JE, Cone-Wesson B, Sininger YS, Goga MP, Folsom RC, et al. Identification of neonatal hearing impairment: Characteristics of infants in the neonatal intensive care unit and well-baby nursery. Ear Hear. 2000; 21(5):373–82.

13. Joint Committee on Infant Hearing 1990 position statement. ASHA. 1991; 33:3–6.

14. Mauk GW, White KR, Mortensen LB, Behrens TR. The effectiveness of hearing programs based on high-risk characteristic in early intervention of hearing impairment. Ear Hear. 1991;12(5):312–9.

15. Chang KW, Vohr BR, Norton SJ, Lekas MD. External and middle ear status related to evoked otoacoustic emission in neonates. Arch Otolaryngol Head Neck Surg .1993; 119(3):276–82. 

16. Danielle S. Holstrum W. Hearing Screening and Diagnostic Evaluation of Children with Unilateral and Mild Bilateral Hearing Loss. Trend Amplif .2008; 12(1):27–34.

17. Stein LK. Factors influencing the efficacy of universal newborn hearing screening. Pediatr Clin North Am .1999;46(1):95–105.

18. Cone-Wesson BDowell RCTomlin D, Aance G, Ming W. The auditory steady-state response: comparisons with the auditory brainstem response. J Am Acad Audiol .2002; 13(4):173–87.

19. Vander Werff KRBrown CJGienapp BA, Gienapp BA, Schmidt Clay KM. Comparison of auditory steady-state response and auditory brainstem response thresholds in children. J Am Acad Audiol. 2002; 13(5):227–35.

20. Zamani A, Daneshjou K, Ameni A. Estimating the incidence of neonatal hearing loss in high risk neonates. Acta Medica Iranica. 2004; 42(3):176–80.

21. Ur Rehman MMando KRahmani A  Imran A, Ur Rehman N, Gowda K, Chedid F. Screening for neonatal hearing loss in the Eastern region of United Arab Emirates. East Mediterr Health J. 2012; 18(12):1254–6.

22. Van Dommelen PMohangoo ADVerkerk PH, et al. Dutch NICU Neonatal Hearing Screening Working Group. Risk indicators for hearing loss in infants treated in different neonatal intensive care units. Acta Paediatr .2010; 99(3):344–9.

23. Hille ETVan Straaten HIVerkerk PHDutch NICU Neonatal Hearing Screening Working Group. Prevalence and independent risk factors for hearing loss in NICU infants. Acta Paediatr. 2007; 96(8):1155–8.