Skip to content
Open navigation

Moyo Fetal Heart Rate Monitor

Moyo is an affordable fetal heart rate monitor designed for intermittent and continuous monitoring.

Moyo is able to detect abnormal fetal heart rate easily, allowing health care providers to take appropriate and timely obstetric decisions earlier on.


  • Moyo is designed for both intermittent and continuous monitoring
  • With a 9-crystal sensor, Moyo can accurately detect FHR within 5 seconds and can differentiate the maternal HR and the FHR.
  • Moyo comes with a 30-minute histogram display of the FHR, as well as an audio-visual alarm if abnormal FHR is detected.
  • Moyo is lightweight and portable and thus can monitor continuously, even while the mother is moving around.
  • Moyo therefore enables healthcare providers to make appropriate and timely obstetric interventions and eases the workload without interrupting existing routines.


Winner of Saving Lives at Birth Grant

Moyo, as part of Safer Births Project in Tanzania, won a prestigious Saving Lives at Birth Grant to validate the device. One of the studies funded by this grant compared Moyo to Pinard, where use of Moyo was associated with (Kamala, 2017):

  • Increased detection of abnormal FHR
  • Increased frequency of fetal heart rate monitoring
  • Increased rate of documentation of maternal parameters during labour
  • And reduced duration of stay in the labour ward

Further studies were done to collect the attitudes and perceptions of women who had worn Moyo continuously during their most recent delivery and perceptions about how it affected care. Results indicated that the use of the monitor positively affected the women’s birth experience (Lafontan, 2018):

  • Moyo provided much-needed reassurance about the wellbeing of the child.
  • The women considered that wearing Moyo improved care due to an increase in communication and attention from birth attendants.


Heart Rate Measurement

Ultrasound Transducer

  • Display range: 50-250 bpm
  • No detectable heart rate or heart rate <50 bpm displayed as "-?-"
  • Accuracy: short term average +/-5 bpm in the range of 50-200 bpm

Maternal HR Electrodes

  • Display range: 30-250 bpm
  • No detectable heart rate or heart rate <30 bpm displayed as "-?-"
  • Accuracy: short term average +/-5% or +/-5 bpm, whichever is greater, in the range of 50 - 150 bpm

FHR Alarm Algorithm

Lost FHR Alarm

  • When no FHR or <50 bpm lasting for 60 seconds is detected by the ultrasound sensor

Abnormal FHR Alarm

  • When <100 bpm or >180 bpm lasting for more than 3 minutes is detected by the ultrasound sensor
  • When between 100-110 bpm or 160-180 bpm lasting for more than 10 minutes is detected by the ultrasound sensor


  • Internal rechargeable battery, Lithium-ion, 3.7 V, 2600 mAh
  • Battery run time (full charge on fresh battery): >10 hours

Ultrasound Transducer

  • Mode: 9-crystal pulsed wave Doppler ultrasound
  • Frequency: 1 MHz
  • Intensity: <5 mW/sq. cm
  • Thermal index (TI) and mechanical index (MI) are always below 1.0


  • Operating temperature: 0-40 degrees Celsius
  • Storage/shipping temperature: -20 to 60 degrees Celsius
  • Operating/storage/shipping humidity: Up to 95% relative humidity, non-condensing
  • Ingress protection: IP41


  • Main body: ABC/PC, stainless steel
  • Ultrasound transducer: ABS
  • Abdominal transducer belt: high elastic polyester, non-latex
  • Neck strap: Polyester, non-latex


  • Size: 96 x 96 x 24 mm (W x H x D, without cable and ultrasound transducer)
  • Weight: 300 g (main unit + ultrasound transducer)


  • There are no serviceable parts

Accessories and Spare Parts

  • Abdominal transducer belt (package of 3)
  • Neck strap (package of 3)
  • Battery charger and cable (5 V USB wall adapter + USB cable, 1.5 m)