One of the most important human senses is hearing—after all, it’s how we listen to the sounds of the world. The newborn hearing screening test was developed to enable early diagnosis in cases of hearing problems, providing the chance for speech development as close as possible to that of a child who hears normally. From around five months of pregnancy, while still in the womb, babies can already hear the mother’s bodily sounds and external voices from the father, mother, and family, with this ability developing like other body functions. In some cases, however, babies are born with hearing issues when this function hasn’t developed as expected.

The newborn hearing screening, or as it is also known, the otoacoustic emissions test, consists of placing a small earphone that emits low-intensity sounds and records the response received by the inner ear. The test should be performed right after the baby is born and is extremely important for helping hearing-impaired babies develop language, especially when detected before six months of age. This test is mandatory and should be performed in the maternity ward before hospital discharge.

Late detection can hinder treatment and reduce the chances of achieving medical goals. Unfortunately, this happens quite often in Brazil, where children are sometimes not diagnosed with hearing impairment until around 3 or 4 years old. By then, much of their development may already have been compromised due to the delay.

Are There Babies at Higher Risk?

There are high-risk babies who, due to family history or problems developed during pregnancy or after birth, particularly need this exam and proper follow-up. These include:

  • Family history of deafness on either the mother’s or father’s side
  • Congenital infections, such as rubella, toxoplasmosis, cytomegalovirus, herpes, and syphilis
  • Premature or low-birth-weight babies
  • Use of ototoxic antibiotics and diuretics

Babies who undergo ICU interventions for longer than 48 hours are also at risk for developing hearing problems. Ear abnormalities and cleft lip and palate are also risk factors, and babies with these conditions should have the hearing screening as soon as they are born. The test is required by law and must be performed on all babies—whether healthy or at risk—so they can receive an accurate diagnosis. The test is painless, and unlike the heel prick test, it does not involve needles or blood collection, and can be performed quickly and even while the baby is sleeping.

Hearing loss can develop over the months, even in babies not initially considered at risk, especially those who were born prematurely. Therefore, any sign of difficulty hearing or symptoms where the baby does not respond to sounds or stimuli should prompt a visit to a pediatrician for referral and evaluation by a pediatric otolaryngologist. The sooner a problem is discovered, the faster and more effective treatment can be to help the baby’s development.

See also: Expanded Heel Prick Test – What Diseases Does It Detect?

Photo: Jacob Johan