[Obstetrical tocography. II. Review of its methodology and a new concept]

The methods employed for measuring pressure have been analysed from the historical and practical points of view. The systems at present in use are criticised and a modification based on catheters with inflatable balloons is described. By this method precise manometry is obtained using a strong material. The patient can unplug the monitoring system without it having to be recalibrated later. Furthermore this system avoids errors which come from movements of the catheter, changes of temperature and accidental increases in pressures. Equally it will stand humidity and sterilisation by heat.