Listening to the Placenta to Detect Pregnancy Complications Early

Farah Deeba – fdeeba@charlotte.edu

University of North Carolina at Charlotte
9201 University City Blvd Charlotte
Charlotte, NC, 28223
United States

Additional Authors: William Hempstead, Hamid Moradi, Mekdes Bezabh, Robert Rohling

Popular version of 2aBAb3 – Quantitative Ultrasound Characterization of the Human Placenta for Detection of Placenta-Mediated Pregnancy Complications
Presented at the 189th ASA Meeting
Read the abstract at https://eppro02.ativ.me/appinfo.php?page=Session&project=ASAASJ25&id=3982940&server=eppro02.ativ.me

–The research described in this Acoustics Lay Language Paper may not have yet been peer reviewed–

Many pregnancy complications begin with subtle problems in the placenta, the organ that supplies oxygen and nutrients to the baby. Can sound waves reveal these hidden problems before they lead to serious health risks? Our research shows that they can: a simple ultrasound scan may help identify placental problems much earlier than today’s clinical methods.

When the placenta fails to provide adequate support, a condition known as placental insufficiency, pregnancies are at higher risk for preeclampsia in the mother, and growth restriction and oxygen deprivation (hypoxia) in the baby. Because these conditions often show no early symptoms, clinicians need a safe, accessible way to assess placental health during routine prenatal care.

To address this need, researchers at UNC Charlotte and the University of British Columbia are studying a technique called quantitative ultrasound (QUS). QUS analyzes the raw sound echoes returning from the placenta during an ultrasound scan. These echoes contain detailed information about tissue structure. When the placenta begins to show signs of insufficiency, its acoustic “signature” changes. QUS can detect these subtle changes that are not visible on a regular ultrasound image. Video 1 shows the raw signals (right) corresponding to an in utero placental image (left) acquired during a third-trimester ultrasound scan. These raw signals contain the acoustic information that QUS analyzes to detect early changes in placental health that may not be visible on a standard ultrasound image.

Video 1. Ultrasound data collected from a 3rd trimester placenta, along with the raw sound-wave signal (RF signal) that QUS analyzes.

To test whether these acoustic signatures reflect real structural differences, we first applied QUS on placentas collected after delivery. Using QUS, which measures how placental tissue absorbs and weakens sound, scatters the echoes, and what are the average sizes of the tissue structures, we found clear differences between healthy and diseased placentas. When these measurements were entered into a simple prediction model, the tool correctly distinguished healthy and diseased placentas with high accuracy showing that QUS can capture structural changes linked to placenta-mediated diseases: preeclampsia and small-for-gestational-age.

Encouraged by these findings, we evaluated QUS during pregnancy, conducted within the Wellcome Leap In Utero Consortium, an international effort to understand and prevent stillbirth. In this in utero study, we scanned pregnant participants in the USA, Canada, UK and Uganda, and analyzed the acoustic patterns of their placentas. QUS measurements were able to identify pregnancies in which babies later experienced oxygen-related distress and were especially accurate when these complications were linked to placental abnormalities confirmed after birth. Figure 2 shows how raw (RF) signals are transformed into a color-coded QUS map, making subtle differences in placental tissue easier to see and compare. These findings suggest that QUS could help clinicians recognize early signs of risk and monitor pregnancies more closely.

Figure 1: Raw sound waves collected during the scan are transformed into a color-coded quantitative ultrasound (QUS) map that highlights acoustic differences within the placenta during pregnancy

Figure 1: Raw sound waves collected during the scan are transformed into a color-coded quantitative ultrasound (QUS) map that highlights acoustic differences within the placenta

Because QUS uses the same sound waves and equipment already found in clinics, it can be integrated into handheld or portable ultrasound devices, making it practical for hospitals, local clinics, and resource-poor settings, where advanced imaging is not available. This flexibility gives QUS the potential to support more equitable prenatal care worldwide. As we continue refining the technology, our goal is to develop a fast, affordable tool that detects placental insufficiency early enough to improve pregnancy outcomes everywhere, including communities with limited access to specialized medical care.

Life-threatening pregnancy disorder detected in placenta with quantitative ultrasound

Andrew Markel – amarkel@tulane.edu

Tulane University, 6823 Saint Charles Ave, New Orleans, LA, 70118, United States

Popular version of 5aBA3 – Quantitative Ultrasound-Based Characterization of Placental Microstructure During Preeclampsia
Presented at the 188th ASA Meeting
Read the abstract at https://doi.org/10.1121/10.0038280

–The research described in this Acoustics Lay Language Paper may not have yet been peer reviewed–

Preeclampsia is a life-threatening pregnancy disorder that currently has no cure and is a significant cause of death for expecting mothers and their babies worldwide. A recent study by researchers at Tulane University and Weill Cornell Medicine has shown that quantitative ultrasound imaging of the placenta may help doctors detect preeclampsia earlier. Through this collaboration, the researchers discovered a connection between quantitative ultrasound images and the size of biological structures in the placenta. This preliminary study in rats also saw a significant difference between normal and preeclamptic placentas using quantitative ultrasound (Figure 1, bottom row), opening the door for potential applications in human medicine.

Figure 1. Comparison between normal ultrasound (top row) and quantitative ultrasound (bottom row) images of a normal placenta (left column) and a preeclamptic placenta (right column) in pregnant rats. Placentas in normal ultrasound images are outlined in red. A 5 mm scale bar is provided in the upper left-hand corner of all images for reference.

During normal pregnancies, the placenta delivers nutrients from the mother to the fetus and undergoes microscopic changes in its structure that allow it to deliver more nutrients as the fetus grows larger. For women with preeclampsia, the placenta fails to develop correctly, resulting in significant microstructural changes that cause high blood pressure, birth defects, and organ failure. The only way that doctors can alleviate the mother’s symptoms from preeclampsia is by delivering the baby and placenta early, which puts the baby at risk for developing complications associated with premature birth.

Ultrasound imaging is the most common method that doctors use to monitor pregnancies, but the ultrasound imaging methods currently used in clinics cannot detect the microstructural changes in the placenta that occur during preeclampsia (Figure 1, top row). Instead, preeclampsia is often detected when the mother has already developed high blood pressure and kidney failure, which can lead to further heart and kidney disease complications in the mother, even after the baby and placenta are delivered. Doctors need a better way to monitor the placenta for preeclampsia so that they can better understand how the disease develops and diagnose at risk women earlier.

Quantitative ultrasound imaging methods apply mathematical models of sound interactions and statistics to quantify the microscopic structural elements’ size, structure, and organization in human organs. With quantitative ultrasound, doctors will be able to diagnose diseases that would be impossible to detect using current ultrasound imaging methods. So, researchers studying the placenta in the Department of Biomedical Engineering at Tulane University decided to team up with researchers developing quantitative ultrasound algorithms in the Department of Radiology at Weill Cornell Medicine to investigate how quantitative ultrasound could help to diagnose preeclampsia. The research team is currently conducting a pilot study with human placentas after birth to determine how quantitative ultrasound images can help doctors diagnose preeclampsia in the clinic. Earlier diagnosis of preeclampsia could have a major impact on the way that doctors study and treat the disease, potentially saving the lives of thousands of women and children all around the world.