Newsletter Fall 2021

Nanotech device can detect risk for placenta accreta spectrum disorder

A multidisciplinary research team from UCLA led by Dr. Yalda Afshar, Assistant Professor of Obstetrics and Gynecology at the David Geffen School of Medicine at UCLA, has developed a new blood test to detect placenta accreta spectrum disorder earlier in pregnancy.

Currently, placenta accreta spectrum disorder is diagnosed by ultrasound in combination with an assessment of a mother's pregnancy history. However, those factors alone are usually not reliable enough to detect cases other than the most severe ones. This new blood test can be performed as early as the first trimester of pregnancy, which allows for early referrals to high- risk maternal-fetal medicine specialists. The preliminary data obtained on more than 100 women, showed that the blood test was 79% accurate in confirming the presence of placenta accreta and 93% accurate in ruling it out if the test was negative result.

Placenta Accreta

The new approach uses a technology called the NanoVelcro Chip, which has been developed over the past 15 years by Dr. Yazhen Zhu and Hsian-Rong Tseng, UCLA professors of Molecular and Medical Pharmacology. Originally created to detect tumor cells in people with cancer, the chip is a postage stamp–sized device with nanowires that are 1,000 times thinner than a human hair and coated with antibodies that can recognize specific cells.

For the new study, the researchers adapted the chip so that it could detect trophoblasts, cells specifically linked to placenta accreta spectrum disorder, in the mother's blood. When a blood sample is tested using the chip, trophoblasts stick to the chip and can be detected under a microscope. An abnormally high count of trophoblasts or a trophoblast cluster in the blood indicates an elevated risk for placenta accreta disorder.

"Early and precise detection of this very high-risk obstetrical problem can greatly improve outcomes for both the mother and baby," said Dr. Afshar, co-first author of the study. "With the unreliability of the current screening methods for placenta accreta, we saw a pressing need to create an easy-to-implement screening that can be conducted early in the pregnancy in all healthcare settings regardless of resources available to patients."

The researchers are exploring ways to refine the test to improve its accuracy and reliability. The team includes experts from many disciplines, including obstetrics, nanotechnology, pathology, engineering, chemistry, microfluidics and biostatistics.

A paper detailing the new method is published in Nature Communications.