How sensitive is my baby's hearing?
     
More sensitive than an adult's - so you should use common sense when exposing a child to loud noises. A good rule of thumb: If you can talk easily over the sound, it shouldn't harm your baby's hearing.

How does a baby normally react to sound?
Initially, your baby's response to sound will depend somewhat on her temperament. Some babies are hardwired to be more sensitive; they may react more to loud noises than babies with calmer personalities.
It also depends on what your baby heard while she was nestled in the womb. Your baby has been listening to the muffled roar of your world since about the 24th week in utero. If, during her nine months' gestation, she often heard her brother running around the house screeching, or her daddy practicing the bagpipes, those sounds became familiar to her. They won't faze her when she encounters them in daily life. In fact, she'll probably be able to sleep right through them. On the other hand, new sounds may startle an infant, causing her to cry. Once she's three months old, however, they may elicit only blinking and, a month later, may prompt her to turn toward its source.

My baby sleeps through everything. How can I tell if her hearing is normal?
   
Babies are amazing creatures: They can sleep right through the telephone ringing and the dog barking. This is very normal, and doesn't indicate that your baby has a hearing problem but, rather, she needs her sleep. It's better to test your baby's hearing when she's awake and alert.

Here are a few quick tests you can do to check her hearing:
 

• If your baby is under three months, clap your hands behind her head. If she startles, she's fine. If she doesn't, repeat a few times.
• If your baby is a bit older, between four and six months, she should have some head control. Call her name to see if she turns toward or reacts to your voice. She might also turn her eyes or head to look for an interesting sound.
• Between six and ten months, your child should respond to her name and familiar environmental sounds, such as the ringing of the phone or the roar of the vacuum cleaner.
• Between ten and 15 months, she should be able to point to a familiar object in a picture book when asked.
• If there's no response to any of these tests, consult your pediatrician. Since the vast majority of babies have excellent hearing, it's probably just a temporary loss caused by a cold. Or she may simply be too engrossed in something else to take notice.

What can hamper a baby's hearing?
Some of the things that can affect hearing include:

• Exposure to prolonged, high-decibel noise like that found near airport runways or at rock concerts.
• Family history of hearing problems.
• Serious problems during birth that may have resulted in a lack of oxygen to the baby.
• Premature birth.
• Prenatal exposure to rubella.
• Some types of birth defects.
• Chronic middle-ear inflammation (otitis media), which may cause scarring in the Eustachian tubes if your child has frequent ear infections. She may also have temporary hearing loss during an ear infection.

Can I do anything to help develop my child's hearing?
Hearing helps children learn about the world and communicate. You can stimulate your baby's sense of hearing by:

• Popping in a CD or turning on the radio. Children love music, so if it seems appropriate, point out the tinkling of the piano and the clanking of the cymbals.
• Talking to your child and reading to her. Nothing stimulates a child's intelligence more than hearing you talk. Don't endlessly bombard your child with words, but if she seems interested, tell her what you're doing. For example, if you're packing her diaper bag, give her a blow-by-blow description of what you're including. When you dress her, name the color and type of garment you're slipping over her head and describe the lacy quality of the socks you're putting on her feet.
• Tuning into what your baby hears and commenting on it. Whether it's the hum of an airplane engine or the purr of a cat, noticing what your baby hears will allow you to help her understand her environment. It might also help you to do the auditory equivalent of stopping or at least slowing down to smell the roses.