Key Takeaways
- Hamilton Health Sciences and St. Joseph’s Healthcare Hamilton are using the sFlt-1/PlGF ratio test.
- The test is used when routine testing cannot clearly confirm or rule out suspected pre-eclampsia.
- Local tracking found 59 of 109 patients received low-risk results between December 2025 and June 2026.
How the New Blood Test Works
The sFlt-1/PlGF ratio test measures two proteins associated with the placenta.
According to Hamilton Health Sciences, the test cannot diagnose pre-eclampsia on its own. Instead, it provides additional information that can help identify patients at low risk and support decisions about monitoring and care.
The test is used when standard tests, scans and examinations cannot provide a clear diagnosis.
Who Is Receiving the Test?
Doctors at Hamilton Health Sciences and St. Joseph’s Healthcare Hamilton have been using the test since fall 2025.
It is being used for patients between 20 and 36 weeks of pregnancy when pre-eclampsia is suspected but cannot be confirmed after routine testing.
The hospitals involved include McMaster University Medical Centre, McMaster Children’s Hospital, West Lincoln Memorial Hospital and St. Joseph’s Healthcare Hamilton’s Charlton campus.
Why Pre-Eclampsia Can Be Difficult to Diagnose
Pre-eclampsia typically develops after 20 weeks of pregnancy.
Symptoms can include changes in blood pressure, headaches and swelling. Some of these symptoms can also occur with other conditions or during pregnancy, making diagnosis more difficult in certain cases.
Early detection and careful monitoring are important because untreated pre-eclampsia can lead to serious complications for both the pregnant patient and baby.
What the Hamilton Results Show
The medical teams implementing the test are also tracking how it performs in local patients.
From December 2025 through the end of June 2026, the team tracked 109 patients who were suspected of having pre-eclampsia but whose diagnoses remained inconclusive after standard testing.
Of those patients, 59 received a low-risk result from the sFlt-1/PlGF ratio test.
Thirty-six of the 59 patients with low-risk results were not admitted to hospital for monitoring, allowing them to return home with their families.
Hamilton Health Sciences says this helped avoid unnecessary hospital stays and deliveries while also reducing pressure on hospital resources.
What Different Results Can Mean
Hamilton Health Sciences says a low-risk result provides up to a 98 per cent chance that the patient will not develop pre-eclampsia in the near future.
An intermediate-risk result is considered inconclusive and may require additional testing and monitoring.
A high-risk result indicates a strong chance of pre-eclampsia and may lead to hospital admission, additional testing and closer monitoring.
Laboratory Collaboration
The test was introduced through collaboration between Hamilton Health Sciences, St. Joseph’s Healthcare Hamilton, the Hamilton Regional Laboratory Medicine Program and Roche, which developed and manufactures the test.
The Hamilton Regional Laboratory Medicine Program operates 31 laboratories across the two hospital networks.
The sFlt-1/PlGF ratio tests are analyzed at a specialized laboratory at St. Joseph’s Healthcare Hamilton. Hamilton Health Sciences says it is one of only two locations in Ontario offering the test.
Could the Test Expand Across Canada?
The test is already used at some larger Canadian hospitals, but Hamilton Health Sciences says it has not yet been widely adopted across the country.
Doctors involved in the program would like to see the test become more widely available for patients whose suspected pre-eclampsia cannot be confirmed through routine testing.
The Hamilton team is continuing to collect data to understand how the test performs and how it can best be incorporated into patient care.
The latest results provide local information about how the test can help doctors make more informed decisions when standard testing leaves uncertainty.