The NASA Tech Briefs of May 1999 described a device that telemeters pressure changes to detect intrauterine contractions. According to the brief:
A biotelemetric system for monitoring key physiological parameters of a fetus and its uterine environment is undergoing development. The main purpose of the monitoring is to detect preterm labor in order to enable timely treatment. At the present stage of development, the system monitors pressure changes and temperature. The pressure changes serve as direct indications of intrauterine contractions that could be associated with the onset of preterm labor. Future versions of the system are expected to monitor additional parameters, including pH and the heart rate of the fetus.