Screen Positive Results

Newborn screening helps find babies who have serious diseases but may seem healthy at birth. When these diseases are found early in life, treatment can help prevent health and developmental problems and in some cases, death.

A “screen positive” result does not mean that a baby has the disease. It means that the baby has a higher chance to have the disease and that more testing is needed to find out for sure.

What happens when a baby screens positive on the newborn screening blood test?

When a baby's blood sample is screen positive for a disease, the health care providers at Newborn Screening Ontario (NSO) refer the baby to specialized follow-up clinics in their region. We call these centres "regional treatment centres". The treatment centre will arrange more testing to find out whether the baby has the disease.

Health care providers at the regional treatment centres will contact the baby’s doctor, midwife, nurse practitioner, or parents to inform them of the results. They will also arrange appointments and tests that are required to find out if the baby has the disease.

Once testing and evaluation are complete, specialists at the regional treatment centre will determine whether the baby has the disease or not. Three possible outcomes of diagnostic testing include:

No further follow-up is needed.

If diagnostic testing rules out the disease for which a baby screened positive, the newborn screening result is considered a false positive result.
In other words, false positive results are when a baby screens positive for a disease, but follow-up testing shows that the baby does not actually have the disease.
False positive results cause unnecessary worry for families but come as a by-product of striving to find every baby who has the disease. Sometimes false positive newborn screening results can be explained, but most often there is no explanation.

The regional treatment centre continues to follow the baby and more testing may be needed.

The specialist physician and team provide follow-up treatment and care for the disease.

If a baby is diagnosed with the disease for which they screened positive, the newborn screening result is considered a true positive result. Health care providers at the regional treatment centre will discuss treatment and management options with the baby's parents.
There is wide variation in the clinical presentation of the diseases that the newborn screen detects. Some babies who have had diagnostic testing indicating that they have a disease will remain healthy or have only very mild symptoms, even without treatment.

The outcome of this evaluation is reported back to the referring physician at NSO, thus concluding the screening process. Parents/guardians may choose not to share this information, in which case they should be encouraged to discuss this with their health care provider or contact us.

The Disease Information section of our website provides information about specific screen positive results.

What happens when a baby screens positive for critical congenital heart disease (CCHD)?

Screening for CCHD happens at the bedside and results are available immediately. Babies who screen positive for CCHD are examined by a physician to determine the cause for the low oxygen level in their blood. The next steps may involve tests, such as an ultrasound of the heart (also known as an echocardiogram) to determine if the baby has CCHD. Please see the CCHD information section for more information about CCHD screen positive results.

What happens when a baby screens positive on the risk factor screen for permanent hearing loss (PHL)?

Please see the hearing loss risk factor screening section of our website for more information about a positive result for congenital cytomegalovirus or genetic risk factors for PHL.

What happens when a baby has pale coloured stool and screens positive for biliary atresia?

Information on biliary atresia and screen positive results can be found on the Biliary Atresia section of our website.

Children’s Hospital of Eastern Ontario
415 Smyth Road
Ottawa, Ontario K1H 8M8

Toll-Free: 1-877-627-8330
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