Analysis of fetal activity and maternal and fetal heart rate using a laboratory minicomputer

Using a PDP-11 minicomputer, a system was developed for real-time acquisition of fetal breathing, body movement, and heart rate data. Analogue event pulses were input electronically to a DR-11 16 channel A/D, D/A interface and the event times were measured using an AR-11 real-time clock. Event times were stored for comprehensive off-line analysis and useful data summaries were also provided on-line. The on-line printouts enabled investigators to examine the quality of the data at the time of the study. The system has resulted in faster data acquisition and analysis and greater accuracy of measurement.