Blood spot
Updated 11 August 2025
Applies to England
This short video explains blood spot screening in newborn babies.
Blood spot screening is recommended by the NHS.
1. Purpose of screening
The purpose of blood spot screening is to find out if your baby has any of a number of rare but serious health conditions.
Early treatment can improve your baby’s health. It can prevent severe disability or even death. If you, the baby’s father, or a family member already have one of these conditions, please tell your healthcare professional straight away.
2. About these conditions
2.1 Sickle cell disease
About 1 in 2,800 babies born in the UK has a sickle cell disease (SCD). These are serious, inherited blood diseases. They affect haemoglobin, a part of the blood that carries oxygen around the body. Babies who have SCD will need specialist care throughout their lives.
People with SCD can have attacks of severe pain and get serious infections. They can also have anaemia (when their bodies have difficulty carrying oxygen). Babies with SCD can receive early treatment. This includes vaccinations and antibiotics to reduce severe illness and infections.
2.2 Cystic fibrosis
About 1 in 2,500 babies born in the UK has cystic fibrosis (CF). This inherited condition affects the digestion and lungs. Babies with CF may find it hard to gain weight and frequently have chest infections. Babies with CF can be treated early with a high-energy diet, medicines and physiotherapy. Although children with CF may still become very ill, early treatment can help them live longer, healthier lives.
2.3 Congenital hypothyroidism
About 1 in 2,000 babies born in the UK has congenital hypothyroidism (CHT). Babies with CHT do not have enough of the hormone thyroxine. Without thyroxine, babies do not grow properly. They can develop permanent serious physical problems and learning disabilities.
Babies with CHT can be treated early with thyroxine tablets. This will help them to develop as expected.
2.4 Inherited metabolic diseases
It is important to let your healthcare professional know if you have a family history of a metabolic condition. Babies are screened for some inherited metabolic diseases (IMDs).
These are:
- phenylketonuria (PKU)
- medium-chain acyl-CoA dehydrogenase deficiency (MCADD)
- maple syrup urine disease (MSUD)
- isovaleric acidaemia (IVA)
- glutaric aciduria type 1 (GA1)
- homocystinuria (pyridoxine unresponsive) (HCU)
About 1 in 10,000 babies born in the UK has PKU or MCADD. The other conditions are rarer, occurring in 1 in 100,000 babies to 1 in 300,000 babies.
Babies with these inherited conditions cannot process certain substances in their food. Without treatment, babies with some of these conditions can suddenly become seriously ill. The symptoms of the conditions are different. Some may be life threatening or lead to severe developmental problems.
They can all be treated by a carefully managed diet. This is different for each condition and may include additional medication.
3. The screening test
When your baby is 5 days old, the healthcare professional will prick your baby’s heel using a special device. They will collect some drops of blood onto a card. Occasionally this may be later than 5 days. The heel prick may be uncomfortable, and your baby may cry. You can help by making sure your baby is warm and comfortable, and by cuddling and feeding them.
Sometimes, a second blood spot sample is required. If this happens, the reason will be explained. It does not necessarily mean there is something wrong with your baby.
4. Safety of the test
There are no risks associated with having this test.
5. Screening is your choice
Newborn blood spot screening is recommended for your baby.
You can choose to have screening for all conditions or specific conditions only.
You can choose to screen your baby for SCD, CF and CHT individually. If want to screen your baby for IMDs, they will all be tested. Screening for individual IMDs cannot be offered.
If you do not want your baby to be screened for any of the conditions, or have any concerns about the test, please talk to your midwife.
Early screening is best as treatment can be started as soon as possible if needed. If you do not want your baby to be screened, and you later change your mind, your baby can still have the test. Babies can be screened up to 12 months of age for all the conditions, except CF which can only be tested up to 8 weeks of age.
6. Possible results
Results for newborn blood spot screening are reported as ‘condition not suspected’ or ‘condition suspected’.
Most results will show that the conditions screened for are ‘not suspected’.
Some will show that the conditions screened for are ‘suspected’. This does not mean your baby definitely has the condition, but they are more likely to have it.
If the screening results suggest a condition is suspected, a healthcare professional will contact you by phone or in person. They will explain what the result means for you and your baby and tell you if there’s anything you need to do.
Your baby will be referred to a specialist for more tests and to start treatment if needed.
Newborn blood spot screening finds some babies who may be genetic carriers of CF, SCD or another red blood cell condition.
Carriers are healthy and do not have the condition. The only time carriers may experience health problems is in rare situations where their bodies might not get enough oxygen. For example, if they were having surgery under an anaesthetic.
If your baby is a genetic carrier, a healthcare professional will contact you or you will get a letter in the post to explain what this means. Your baby will not need any treatment but may need further tests. Screening does not detect all carriers.
7. Getting my results
If one of the conditions screened for is suspected, you will be contacted by a specialist clinical team. This is to explain the results and offer your baby further testing. Some of these further tests need to be undertaken quickly. You should not ignore any attempts to contact you from the specialist team.
If none of the conditions screened for are suspected, you should receive the results by letter or from your health visitor within 6 weeks.
The results should be recorded in your baby’s personal child health record (‘red book’). Please keep this safe and bring it with you to any further appointments.
8. My baby’s blood spot card and data after screening
After screening, blood spot cards are stored for at least 5 years and may be used:
- to check the result or for other tests recommended by your doctor (if the results could affect the health of your baby, you will be contacted)
- to help improve the screening programme or testing methods for conditions already approved for screening in England (if the results could affect the health of your baby, you will be contacted)
- for research to help improve the health of babies and their families in the UK (this will not identify your baby, and you will not be contacted)
In addition, there is a small chance that researchers may want to invite you or your child to take part in information gathering linked to the newborn blood spot screening programme. Researchers undertaking any additional studies would explain what is being done and you would then be asked if you wish to take part in that study. Please let your midwife know if you do not want to be contacted to discuss taking part in any additional information gathering.
All use of the blood spot cards is governed by the code of practice. Any research will have been approved by an independent research ethics committee.
Find more information and details of support groups on NHS.UK.