Newborn Tests and Procedures

Once your baby is born, you will be asked to make decisions about a number of newborn health assessments, procedures and tests. These procedures are presented as being routine, but you are able to choose whether or not you wish to engage with them as a parent. Your midwife or doctor will offer your baby a full physical assessment within the first three days. Babies born in hospital will also be offered a hearing screening test before discharge. Somewhere between day 3 and 5, you will be offered the Newborn Screening test which screens for a number of neonatal metabolic and genetically inherited conditions. 

Newborn Health Assessment

Within the first 72 hours after your baby’s birth your midwife will offer to give your baby a full physical examination. As she examines your baby she will tell you about some of the things you can keep an eye on in order to monitor your baby’s health.

The newborn examination involves looking carefully at and palpating parts of your baby’s body, for example the chest and abdomen. It also involves listening to the internal sounds of your baby’s body, such as your baby’s breathing and heart sounds and surprisingly enough, their bowel sounds.

The examination includes checking your baby’s:

• Weight, length and head circumference
• Temperature
• Heart and lungs
• Skin
• Head and neck
• Shoulders, arms and hands
• Abdomen
• Genitals
• Hips, legs and feet

 

Hearing Screening Test

All newborn babies in Australian maternity hospitals are offered a hearing screening test. Approximately 1 in every 1,000 babies will have a permanent, moderate, severe or profound hearing loss in both ears at birth.

 

The test that will be offered to your baby depends upon which state you live in, for example in Victorian hospitals, an Automated Auditory Brainstem Response (AABR) test is performed for the hearing screen. 

 

How the test works:

• The baby’s ears are covered with single-use adhesive ear couplers.
• Once connected to the earphones, the couplers emit a series of soft 'clicking' sounds. 
• There are 3 sensor tabs that are placed on the baby’s neck, shoulder and forehead that measure activity in the baby’s auditory nerve in response to the sound being played. 
• The AABR unit makes a statistical calculation based on the responses recorded to determine the screen result.

In some Australian states, an alternative form of hearing screening is performed using Transient Evoked Otoacoustic Emissions (TEOAE). 

 

A well-functioning cochlea not only receives sound, but also emits sounds of low-intensity. These sounds are called otoacoustic emissions (OAEs), and this is what the test aims to capture. The cochlea produces these sounds, along with its outer hair cells, as they respond to the sound stimulus by expanding and contracting.

 

The test is performed by placing a probe in the external ear canal that emits soft sounds to stimulate the cochlear.  Within this probe is a sensitive microphone that is able to detect any outer hair cells auditory response to this initial stimulus. In order to pass the screening test, the strength of the recorded responses must fulfil certain criteria.  

 

The screen can also be done in an outpatient setting if you and your baby are discharged prior to being screened. 

 

Advantages

• Newborn hearing screening aims to identify babies born with a hearing impairment independent of whether they are at risk of a hearing loss.
• The technology used in newborn hearing screening is quick, easy and reliable, and the result can be given straight away.
• The AABR is a fully automated test and is painless and non-invasive for the baby. Both ears can be checked simultaneously and the test takes an average time of about 4-7minutes. 
• A baby can be as young as 6 hours of age for the screen to be undertaken. 
• The hearing screen can be performed on premature babies (34 weeks corrected age or greater), and those admitted to the Intensive and Special Care Nursery. The hearing screen for NICU/SCN baby is performed close to discharge.

Disadvantages

• The hearing screen is not a diagnostic test; therefore any positive results require referral for a diagnostic audiology assessment.
• If your baby is unsettled or there is vervix or amniotic fluid in their ear at the time of the test you may be referred to the outpatients clinic to have the screening test performed.

 

Newborn Screening

The Guthrie’s Test or Heal Prick Test enables your healthcare provider to screen your baby for a wide variety of neonatal metabolic conditions. These include:

• phenylketonuria
• congenital hypothyroidism
• cystic fibrosis
• MCADD
• Galactosaemia – (except Victoria)
• 20 additional rare metabolic conditions.

Most of these conditions are relatively rare, however if they are diagnosed early, treatment can begin immediately and this has a tremendous impact on the outcome for your baby. If left untreated these metabolic disorders and conditions result in physical and mental disability.

This Heal Prick or Guthrie's test is offered to your baby between 3 to 5 days after the birth. The test might be offered to you whilst you are in hospital or if you are at home, a midwife visiting your home will generally perform this test. The midwife uses a special device which includes a small needle, to prick the heal of your baby's foot. Drops of your baby's blood are placed onto several circles of absorbent filter paper on a Guthrie’s Test card. The blood is then examined using microbiological techniques.

What is phenylketonuria

About 1 in 10,000 to 1 in 14,000 babies born in Australia has phenylketonuria (PKU). Babies with this inherited condition are unable to process a substance in their food called phenylalanine. If untreated, they will develop serious, irreversible, mental disability. Screening means that babies with the condition can be treated early through a special diet, which will prevent severe disability and allow them to lead a normal life. If babies are not screened, but are later found to have PKU, it may be too late for the special diet to make a real difference.

 

What is congenital hypothyroidism?

About 1 in 4,000 babies born in Australia has congenital hypothyroidism (CHT). Babies with CHT do not have enough of the hormone thyroxine. Without this hormone, they do not grow properly and can develop serious, permanent, physical and mental disability. Screening means that babies with CHT can be treated early with thyroxine tablets, which will prevent serious disability and allow them to develop normally. If babies are not screened and are later found to have CHT, it may be too late to prevent them becoming seriously disabled.

 

What is cystic fibrosis?

About 1 in 2,500. babies born in Australia has cystic fibrosis (CF). This inherited condition can affect the digestion and lungs. Babies with CF may not gain weight well, and have frequent chest infections. Screening means that babies with CF can be treated early with a high energy diet, medicines and physiotherapy. Although a child with CF may still become very ill, early treatment is thought to help them live longer, healthier lives. If babies are not screened for CF and they do have the condition, they can be tested later but parents may have an anxious time before CF is recognised.

 

Galactosaemia

About 1 in 50,000 babies born in Australia will have Galactosaemia. Babies with this inherited condition have problems breaking down the sugar galactose. This can lead to liver disease, intellectual impairment and septicaemia in the worst cases.

 

Advantages of the test

• Enables early diagnosis of metabolic and endocrine disorders which though rare, if left undiagnosed and untreated generally lead to physical or mental impairment.

 

Disadvantages of the test

• The heel prick may be uncomfortable for your baby and they may cry. If you choose to engage with the test, you could support your baby by breastfeeding or cuddling them whist they have the test.

• Antibiotics may interfere with the screening test, if you choose to engage with the test and you are on antibiotics and are breastfeeding your baby, you should inform the midwife.