The proportion of newborns screened for hearing loss in the US has climbed steadily in recent years, hitting 95% by mid-2006.
But a third of them do not turn up for follow-up evaluation they could be susceptible to delays in language development that they might never overcome, says author Karl White, director of the National Center for Hearing Assessment and Management at Utah State University.
About 3.8 million newborns are screened for hearing loss each year, according to the Centers for Disease Control and Prevention. The screening takes about nine minutes and should be done before 1 month of age, preferably before the baby leaves the hospital, according to the CDC.
About 2%, or 76,000 babies, don't pass and are referred for a diagnostic assessment of their hearing. Additional testing is needed to determine whether they are among the one to three babies per 1,000 who actually have hearing loss, the CDC says.
Until recently, only about half of babies who failed the screening were reported as having the additional testing, but that proportion rose to two-thirds in the past year, White found. "One year doesn't make a trend," cautions White, whose study was paid for by the Maternal and Child Health Bureau of the Department of Health and Human Services. "We think we're getting better, but there's still a huge problem here."
One problem is a shortage of audiologists who do diagnostic tests on babies, White says. Reimbursement rates are the same whether the patient is an adult or an infant, he says, even though adults are easier to test.
Among other contributing factors, White says, are "parent expectations and parent lack of understanding." As far as most parents are concerned, he says, hearing is a dichotomy: "You either have it or you don't." But babies who startle at loud noises, such as pots slamming, might not be able to hear lower-decibel sounds, White says.
Newborn hearing screening programs have lowered the average age of diagnosis to 3 to 4 months, he says. But if babies who fail screening don't receive follow-up testing, White says, they won't be diagnosed until they're around 2 or 3 years old.
By then, language and social skills are lagging, he says, and they might never catch up: "There are deaf people who are identified at 6 years of age who turn out to be incredibly successful, but, on average, that doesn't happen."