New Ultrasound Technique Detects Fetal Circulation Problems in Placenta

Pregnant black woman's belly being scanned with ultrasound instrument held by a white hand.

An NIH-funded advance could alert physicians to increased need for fetal monitoring, early delivery.

Photo: MONKEYBUSINESSIMAGES/GETTY

NIH-funded researchers have developed a new ultrasound technique to monitor the placenta for impaired fetal blood flow early in pregnancy. The method could help diagnose circulation problems in the placenta that can harm the fetus and would otherwise go undetected until late in pregnancy.

The technique, which uses conventional ultrasound equipment, relies on subtle differences in the pulsation of fetal blood through the arteries at the fetal and placental ends of the umbilical cord, potentially enabling physicians to identify placental abnormalities that impair fetal blood flow and, if necessary, deliver the fetus early.

Researchers tested the new technique with ultrasound scans on women between the 26th and 32nd weeks of pregnancy and diagnosed those with circulatory problems in the maternal or fetal part of the placenta. After the women gave birth, the diagnoses were verified by comparing them to the results of physical examination of the placentas they delivered. Among them, 40 women had placentas without circulation problems, 16 had placentas with fetal circulation problems, and 30 had maternal placenta circulation problems.

The study, led by Dr. John G. Sled of the Hospital for Sick Children in Toronto and funded in part by NICHD, appears in eBioMedicine.