SHANGHAI, March 7(Xinhuanet)-- More than 90 percent of newborns in Shanghai received hearing tests in 2004, according to the city's Children Hearing Clinical Center. The results can help infants receive treatment if needed.

The center said about 260,000 babies were born in 2002-2004, and 233,800 of them have received hearing tests.

Infants with normal hearing ability learn to speak when they are four to nine months old and no later than 11 months, which is a key signal of their language learning ability.

Infants with severe hearing problems cannot learn to speak, because they don't hear people talking.

If hearing problems can be detected at an early age, language stimulation can be set up by using audiphones and electronic acoustic devices.

About 382 newborns in the city have been found to have hearing problems since 2001, 1.41 percent of the total tested. Most have received medical treatment and now have some hearing and speaking ability.

There are about 100,000 babies born in Shanghai annually.