A portable recorder for long-term fetal heart rate monitoring

A PIC17C44 microcontroller development board and a real-time algorithm were developed with the capability of monitoring the fetal heart rate (FHR) as well as recording both the FHR and maternal heart rate for long-term. This paper describes the development of the microcontroller board and implementation of a real-time algorithm which were used to develop the portable recorder. Two set-up were developed. One setup was used to implement the algorithm in the PIC17C44 microcontroller board. Second set-up was developed for the assessment of the reliability of processed heart rates. A large number of clinical tests have shown the very good performance of the developed monitor in comparison with FHR curves simultaneously recorded with IFM-500 Doppler ultrasound fetal monitor. Statistical comparison was done and showed nonsignificant difference in mean ðp 1⁄4 0:05Þ; correlation coefficient ðr 1⁄4 0:8–0:92Þ and low PRD (5–15). q 2002 Published by Elsevier Science B.V.