The first days after birth are filled with big emotions and new impressions. Amid all the beauty, something important also happens for your baby's health: newborn screening.
Newborn screening is a voluntary health programme offered to all newborns. The goal is to detect rare but serious conditions as early as possible, so that treatment can begin before the baby shows symptoms.
Here you will find an overview of what happens, what is tested for, and what occurs if the screening reveals something unexpected.
What Is Newborn Screening?
Newborn screening is a national health programme offered to all newborns. In most countries, the programme is coordinated through a dedicated newborn screening centre or national laboratory.
The screening consists of several parts:
- Heel prick blood spot test
- Pulse oximetry (oxygen level measurement)
- Physical examination within the first days of life
- Hearing test (otoacoustic emission test, OAE)
The programme is consent-based. This means that as parents you decide whether your child is screened, but participation rates are very high and almost all families choose to take part.
The Heel Prick Test
The best-known element of newborn screening is the heel prick test. A small blood sample is taken from the baby's heel as soon as possible after 48 hours following birth.
Blood drops are placed on a special filter card and sent to the screening laboratory for analysis. The sample is analysed using mass spectrometry, immunoassay and quantitative PCR.
The heel prick hurts a little, but it is over very quickly. You are welcome to hold your baby close or breastfeed during the test. This provides comfort and reduces pain.
Which Conditions Are Tested For?
Newborn screening programmes typically screen for 30 or more rare conditions and groups of conditions. These include:
- Metabolic disorders (around 21 conditions) — defects in the breakdown of organic acids, fatty acid oxidation and amino acids
- Endocrine conditions (2 conditions) — congenital hypothyroidism and congenital adrenal hyperplasia (CAH)
- Cystic fibrosis — a condition affecting the lungs and digestion
- Severe combined immunodeficiency (SCID) and other serious T-cell deficiencies
- Spinal muscular atrophy (SMA) — a condition affecting the nerve cells that control muscles
- Metachromatic leukodystrophy (MLD) — a rare neurological condition
- Sickle cell disease — a haemoglobin disorder
- Remethylation defects and distal urea cycle defects
Although each individual condition is rare, approximately 1 in every 1,000 babies born will have one of the conditions screened for.
Babies are usually born without signs of disease. Screening is therefore the only opportunity to detect these conditions early, so that treatment can begin before the baby develops symptoms.
A Success Story
Newborn screening began in many countries in the 1960s with phenylketonuria (PKU). This screening has prevented serious brain damage in hundreds of thousands of children worldwide. The oldest of these individuals are now fully grown adults living healthy lives.
Pulse Oximetry — Oxygen Level Measurement
Shortly after birth, the oxygen saturation in the baby's blood is measured using pulse oximetry. A small sensor is placed on the baby's foot or hand.
The test is completely painless and can detect serious congenital heart defects that were not picked up during pregnancy or at the clinical examination after birth.
Physical Examination
All newborns receive a physical examination within the first one to three days of life. The doctor checks, among other things:
- Heart and lungs — listens for murmurs and checks breathing
- Hips — examines for developmental dysplasia of the hip (DDH)
- Eyes — checks the red reflex (rules out congenital cataracts)
- Genitalia — checks that development is normal
- Palate — checks for cleft palate
- General assessment — reflexes, muscle tone, skin colour and overall condition
The hip examination is especially important. Developmental dysplasia of the hip occurs in approximately 1 in 100 newborns, and early detection is crucial for successful treatment.
Hearing Test
Most hospitals offer newborn hearing screening. The test is called otoacoustic emission (OAE) testing and measures whether the inner ear sends out sound signals in response to sound.
The test is quick and painless. It is often done while the baby sleeps. A small probe is placed in the baby's ear, and the instrument records whether the ear responds normally.
If the test does not give a clear result, this does not necessarily mean the baby has a hearing problem. Fluid in the ear canal after birth can affect the result. The baby will then be called back for a repeat test.
What Happens If the Screening Shows Something Abnormal?
It is important to know that a positive screening result does not necessarily mean the baby is unwell. Screening is a filter that identifies babies who need further investigation.
If the heel prick test shows abnormal results, you will be contacted promptly. Further tests will clarify whether the baby actually has the condition. In premature babies, results suggesting a condition can sometimes occur without the condition being present.
If you are contacted after the screening, it means the healthcare system is doing its job. Follow-up tests will quickly clarify whether your baby needs treatment.
If a condition is confirmed, your baby will be referred to specialists who will start treatment as early as possible. For most conditions, effective treatments are available that can prevent serious health consequences.
A normal screening result means with high probability that the baby does not have any of the conditions screened for. However, the screening result does not say anything about the risk of other conditions.
Timeline of Examinations
| Timepoint | Examination |
|---|---|
| First day of life | Pulse oximetry, initial physical exam |
| Days 1–3 | Complete physical examination |
| After 48 hours | Heel prick blood spot test |
| First weeks of life | Hearing test (OAE) |
| 6–8 weeks | First well-baby check with pediatrician |
Frequently Asked Questions
Is newborn screening mandatory?
No, newborn screening is voluntary and based on informed consent. However, participation rates are very high and almost all parents choose to take part. Healthcare professionals strongly recommend that all babies are screened.
Does the heel prick hurt?
The baby will feel a small prick, and many babies cry briefly. Skin-to-skin contact with a parent and breastfeeding during the test reduces pain. The whole procedure is over in a few seconds.
How long does it take to get results?
Most samples are analysed quickly. If everything is normal, you will usually not hear anything. If follow-up is needed, you will typically be contacted within 1–2 weeks. If an acute condition is suspected, contact will be made much sooner.
What happens to the blood sample afterwards?
Blood samples are stored at the screening laboratory. They may be used for quality assurance and research, but only after approval from an ethics committee. Parents can request that the sample be destroyed.
Read More
- Well-baby checks — what happens?
- The first week home with a newborn
- Skin-to-skin with a newborn — why it matters
- Vaccines for children — complete overview