The U.S. Food and Drug Administration recently approved the marketing of the Nellcor N-400 Fetal Oxygen Saturation Monitoring System, a fetal pulse oximeter. The American College of Obstetricians and Gynecologists Committee on Obstetric Practice cannot endorse the adoption of this device in clinical practice at this time because of concerns that its introduction could further escalate the cost of medical care without necessarily improving clinical outcome. The committee recommends that prospective randomized clinical trials be conducted to evaluate the clinical use of this new technology in conjunction with fetal well-being assessment.