• Posted January 25, 2024

High-Tech Ultrasound Might Predict Risk for Premature Delivery

Ultrasound scans that pick up "microstructural" changes in a woman's cervix could point to her having a higher risk for preterm birth, researchers report.

The scans were done as early as week 23 of pregnancy and could help assess risks for "preemie" delivery, even among first-time moms.

Between 10% and 15% of births occur before term.

“Today, clinicians wait for signs and symptoms of a preterm birth,” such as a ruptured membrane, explained study lead author Barbara McFarlin. She's professor emeritus of nursing at the University of Illinois Chicago (UIC).

“Our technique would be helpful in making decisions based on the tissue and not just on symptoms," she said in a UIC news release.

As McFarlin's team explained, right now the only clue that a pregnancy might end in premature birth is a woman's prior birth history. That means doctors cannot predict premature delivery in women giving birth for the first time.

McFarlin and her colleagues have for years been working on fine-tuning ultrasound technologies, looking for hints that a woman may not deliver at term.

The form of scan used in the new study is called "quantitative ultrasound."

Instead of just relying solely on a visual image, doctors also use radiofrequency data gleaned from the ultrasound to gauge the density of various tissues.

McFarlin first hit upon the idea as a graduate student in nursing, while she was working as a midwife and sonographer. She noticed that the cervix appeared differently in scans of women who later went on to deliver prematurely.

"No one was looking at it," she said. So, McFarlin and other colleagues studied the pregnancies of 429 women who gave birth without induction.

Using quantitative ultrasound to spot micro-structural changes in cervical tissue, McFarlin's group found the scans were effective in predicting which first-time moms would or would not deliver prematurely.

The strategy was even more effective among mothers who had given birth before.

Combining data from the ultrasound plus any prior history of premature birth was more effective in predicting a subsequent premature birth than using either measurement alone, the investigators found.

How might the ultrasound test change obstetric practice?

According to the researchers, if doctors knew at 23 weeks gestation that there was a higher likelihood for early delivery, they'd arrange more frequent appointments to monitor the health of the fetus.

The new study could also be a jumping-off point to “start studying processes by which you might be able to prevent or delay preterm birth," said study co-author Bill O'Brien, a professor of electrical and computer engineering at the University of Illinois Urbana-Champaign. For years, O'Brien has been investigating how quantitative ultrasound data might further research.

The findings were published Jan. 24 in the American Journal of Obstetrics & Gynecology.

More information

Find out more about preterm delivery at the U.S. Centers for Disease Control and Prevention.

SOURCE: University of Illinois Chicago, news release, Jan. 24, 2024