A computerized fetal monitoring system was developed at the Cedars-Sinai Medical Center in Los Angeles, California, USA. It utilizes unmodified fetal monitors feeding fetal heart rate and uterine pressure data into a minicomputer. The overall accuracy on internal monitoring is 91%. The concept of on-line computer analysis of fetal monitoring records has met with clinical acceptance and is utilized for all patients in labor at the Cedars-Sinai Medical Center.