FDA approves STAN fetal heart monitor.(News)

A fetal heart monitor that provides an analysis of the fetal ECG during labor has won the approval of the Food and Drug Administration almost 4 years after it was originally rejected for use in the United States.

The American College of Obstetricians and Gynecologists is standing firm, however, in its refusal to endorse the STAN S31 fetal heart monitoring system "until it's proved efficacious" in everyday clinical use.

The device, which is used in 22 countries, is now labeled for use in the United States as an adjunct to standard electronic fetal monitoring (EFM) for determining "whether obstetric intervention is warranted when there is increased risk of developing metabolic acidosis." Physicians and other clinicians who use the device, the labeling says, must be certified and credentialed in its use.

The new system monitors the fetal ECG and heart rate via a scalp electrode, automatically identifying and analyzing T-wave and ST-segment changes, which reflect myocardial ability to respond to hypoxia.

When the STAN system was initially reviewed in 2002, members of the FDA's Obstetrics and Gynecology Devices Panel agreed that findings from a randomized Swedish trial of almost 5,000 women in labor demonstrated its safety and effectiveness.

Among women who were monitored with both the STAN monitor and conventional monitoring, as opposed to conventional monitoring alone, metabolic acidosis was reduced by 54%, and operative deliveries for nonreassuring fetal heart rate were reduced by 19%. Moderate and severe neonatal encephalopathy were also significantly reduced.

The panel recommended nonapproval, however, citing concern about differences between Sweden and the United States in labor management and medical terminology. The FDA asked the manufacturer to conduct bridging studies to show that U.S. clinicians could learn the STAN system.