Newborn screening test
All parents are offered the opportunity to have their children screened for a number of rare disorders that can be more easily treated if detected early. The "newborn screening" test is performed within the first 48 to 72 hours after birth. You may also hear it called the "heel prick" test.
Newborn screening tests are free. Tests are not mandatory, and verbal or written consent (depending on the state/territory) is required from the child's parents before the heel prick test is performed.
You will be given an information booklet before the sample is collected, to allow for discussion and obtain your consent for the collection and testing. Parents may decline testing on behalf of their child, but this may unnecessarily put the child's health at risk.
Most children who are screened will not have any of the conditions, but for the small number who are screened, the benefits of screening are enormous. Early treatment can improve their health and prevent severe disability or even death.
How is the test done?
If the parents agree to the test, the midwife or nurse will perform the test by pricking your baby's heel and placing a few drops of blood on special filter paper.
A heel prick is not a comfortable procedure for your child. The best thing you can do to relieve pain is to rest and hold your child during the test. Breastfeeding has also been shown to help soothe your child. There are a number of other techniques you can use to reduce the pain your child may experience.
The filter paper is allowed to dry and then sent to a newborn screening lab where several different tests will be performed.
What is being checked?
Newborn screening helps identify a range of conditions, including:
Phenylketonuria (PKU) - Phenylketonuria is a rare condition that affects approximately 1 in 10,000 babies. A child with this condition cannot properly use one of the building blocks of protein called phenylalanine, which builds up in the blood and causes brain damage. This rare genetic condition can cause severe learning disabilities. Early treatment with a special diet can prevent disability and allow children to live normal lives.
Congenital hypothyroidism (CHT) affects approximately 1 in 3,500 babies. It results from the thyroid gland not developing properly. Early treatment with daily thyroid hormone results in normal mental and physical development.
Cystic fibrosis (CF) - 1 in 2,500 babies has cystic fibrosis. In CF, the mucus produced in the intestines and lungs is thicker than normal. This causes inflammation in the lungs. In the intestines, it can lead to difficulties digesting food properly. The newborn screening test detects about 95% of babies with CF, but it also detects a small number of babies who are carriers of CF. Babies who test positive will need a sweat test at around 6 weeks of age to determine if the baby has CF or is just a healthy carrier. A healthy carrier is unaffected by CF and their body functions normally.
Galactosaemia is an extremely rare disorder that affects only 1 in 40,000 babies. The disorder results from a buildup of galactose (a type of milk sugar) in the blood. Prompt treatment with special galactose-free milk will prevent serious illness. Without treatment, the baby may become seriously ill and die.
Other rare metabolic disorders - Blood can be tested in a heel prick test for a group of very rare metabolic disorders, such as defects in the oxidation of amino acids, organic acids, and fatty acids. Together, these disorders occur in approximately one in 4,000 babies and are extremely rare. These conditions can often be treated with specialized care and diets.
Get results
All of the disorders mentioned in this article are rare, and results are normal in most children. Parents should only be contacted if there are concerns about test results.
A small number of children will need a second blood test. This is usually because the first test didn't give a clear result. Most children's second tests will give normal results, and your doctor will be notified.
If any of the tests show a positive result and your child is thought to have one of these conditions, you will be notified as soon as possible. Your child may need further testing to confirm the results, and you may be scheduled to see a specialist to begin appropriate treatment.
Storage of newborn screening samples
The National Advisory Board for Pathology Certification requires that newborn screening samples be stored. After the dried blood spot test, they will be stored in a secure, locked location until the child turns 18. In some states, you can request the card's return after two years.
The stored sample is kept to allow for quality control, and can be used for ethics committee-approved research after removing identifying information.
The sample may also be used for further testing at the request of the parent or guardian to provide new medical information for the benefit of the family. After a specified period (depending on the state/territory), the samples will be destroyed.