For hospital-born babies, the test normally takes place within a day or two of being born. For babies born at home or with a midwife, it’s suggested they go for a newborn screening test before they are a month old. In the province of Ontario, for example, “Babies born by vaginal birth are screened at a minimum of 15 hours after birth and 22 hours after a C-section,” says infant hearing screener Kim Fraser. Waiting gives the baby time to clear out some of the mucus or fluid that can be in the ear canal from birth.
In the hospital, a screener, as opposed to a doctor or a nurse, will perform the test right in front of you, usually right in your hospital room. Baby needs to be completely quiet for the test—asleep is ideal. So if your newborn is feeding or fussing, the screener will probably come back later.
The test takes about five minutes, and isn't invasive or painful. The tip of a tiny rubber probe shaped like a letter ‘T’ will be placed into your sleeping baby’s ear for just a few seconds. The probe produces a soft sound and a machine records reactionary sound waves that bounce back.
If a baby doesn’t pass the first test, the screener will do a stage two test right then and there if the baby is quiet. This test can take up to 10 minutes. “I get two attempts with the stage one screening test, and if the baby doesn’t pass on the second attempt, then we refer baby to the stage two test,” said Fraser, who tests up to 5,000 babies every year at ErinoakKids Centre for Treatment and Development in Brampton, Ont., as well as at various community clinics and hospitals in the Greater Toronto Area.
The second test measures any brain activity responding to a sound from another small probe placed in the ear. Small electrode sensors are also placed on baby’s head and they should still be asleep.
If your baby doesn’t pass that second screening test, they might have to come back to the hospital or visit a community clinic in a week or two for another screening. If that one fails too, then you'll likely be referred to a paediatric audiologist for diagnostic testing to determine if there is, in fact, hearing loss, and if so, what is causing it and its impact on baby’s hearing.
This test usually happens around three months of age and the diagnostic testing can take about two hours. “Baby has to be asleep during this test and we know that can make parents anxious so we encourage them to make an appointment around feeding time or just before a sleepy time,” says Jan Pepper, the clinical operations manager at ErinoakKids and manager of the Ontario Infant Hearing Program in Central West Region. She adds that it has to be very quiet, so parents are encouraged to feed their babies before the test but not during it, as the sucking noise is too loud.
Just because your child is referred to an audiologist for further testing does not mean they have permanent hearing loss. It means further testing is needed to find out why they didn’t pass the screening test. Sometimes it’s just fluid or air in the ear canal.
In Canada, less than 2 percent of babies fail the screening tests and go on for a full diagnostic test. Of those, less than half are diagnosed with some degree of hearing loss. So there could be hearing loss in one or both ears, it can vary in the level of hearing loss or there could be no hearing loss at all.
If hearing loss is confirmed by an audiologist, many services come into play to support the family and the child, says Pepper. “Some families choose to access technology like hearing aids or cochlear implants; others choose to learn sign language. The goal is to have a plan for treatment and therapy by the time the child is six months old.” In some areas, families are also connected with a social worker who can help them find parent coaching to cope with learning that their baby has a hearing loss or identify funding options for hearing aids, if needed.
Research shows that babies learn language by listening and by imitating their parents and caregivers and when language development starts to happen, even sign language, it allows babies to develop communication, listening and early literacy skills, Pepper added.
Not every Canadian infant has access to early testing for hearing loss and the screening process is different in every province, according to the Canadian Paediatric Society. The infant hearing screening programs in Ontario and B.C. are leaders and most maritime provinces have wide-reaching screening programs in place but in provinces like Alberta, Saskatchewan and in the northern provinces and territories, screening is not happening throughout. Manitoba’s screening program has only been underway for a year and even in Quebec, a pilot project was announced in 2009 and since then healthcare professionals have been working to implement it across the province.
“We know that hearing loss is one of Canada’s most common birth defects,” said Anne-Marie Hurteau, a pediatric audiologist at Montreal Children’s Hospital who was involved in the development of the province’s infant hearing program. “One baby in 1,000 is born with a significant hearing loss and six in 1,000 are born with a lesser degree hearing loss but still significant. If we screen and identify a hearing loss early on and treat it, we can completely change the trajectory of the development of that child.”