Is your baby “measuring small”? First-in-Canada approach provides best care

Sunnybrook is the first Canadian hospital using a device, called a computerized heart rate monitoring tool (cCTG), for pregnancies where a baby is not growing well. The technology allows our care team to have as much information as possible to provide the safest care for pregnant patients and their babies. Dr. Nir Melamed, a maternal fetal medicine specialist, answers some questions about why it’s a big boost for care.

What causes a baby to “measure small”?

“Measuring small” or “measuring small for gestational age” may be perfectly normal; but at times it may be because there is something keeping the baby from growing properly. As a high-risk obstetrician, it’s my job to try to figure out if there’s a problem, and what it is.

Fetal growth restriction, which occurs in about ten per cent of pregnancies, is often caused when there’s an issue with the placenta , which is responsible for bringing nutrients and oxygen to the unborn baby. Without the proper amount of nourishment, the baby can be small for its age. This condition carries serious risks for the baby, including stillbirth, so we need to carefully monitor the baby’s well-being and determine the best timing for delivery.

How does cCTG help?

The cCTG device analyzes the fetal heart rate using advanced technology, and is more precise and reliable than traditional fetal monitoring (which relies on visual interpretation of fetal heart rate patterns). Ultimately, it helps us avoid delivering babies too early when it's not necessary, while also making sure we don't wait too long to intervene when the baby is at real risk of stillbirth.

Sunnybrook implemented a pilot using the technology, showing the device is easy to use and can fully replace the standard fetal heart rate monitoring. Our high-risk care team found the results from the pilot very helpful, saying cCTG increased their confidence in making important decisions about when to deliver.

Can you explain what it’s like for a pregnant patient?

The experience is exactly the same as standard fetal heart rate monitoring. The same types of monitor sensors are placed on the abdomen and held in place with elastic straps. The only difference is what happens behind the scenes: cCTG includes a built-in computer that analyzes the baby’s heart rate using advanced algorithms. This provides objective, quantitative, and reproducible data, rather than relying on the more subjective visual interpretation of fetal heart rate patterns, as in the case of the standard monitors.

What are the benefits for patients and babies?
The biggest benefit is that it helps us make more precise and personalized decisions about when to deliver a baby that is growth-restricted. By providing precise information about how the baby is coping in the womb, cCTG allows us to balance the risks of delivering too early with the risks of waiting too long, thereby optimize the baby’s outcome. This means we can often avoid unnecessary early deliveries, which carry considerable risks for the baby. At the same time, it helps us pick up true signs of fetal distress more reliably, so we can intervene at the right time and potentially prevent serious complications.