Doppler fetal monitor or Doppler fetal heart rate monitor is a hand-held ultrasound transducer used to detect the heart beat of a fetus during prenatal care exams. It uses the Doppler effect to provide an audible simulation of the heart beat. Some models also display the heart rate in beats per minute. Use of this monitor is sometimes known as Doppler auscultation.
A Doppler fetal monitor provides information about the fetus similar to the information a fetal stethoscope provides. One advantage of the Doppler fetal monitor over an acoustic (not electronic) fetal stethoscope is the audio output, which allows people other than the user to listen to the heartbeat. One disadvantage is that is it hard for non-professionals to distinguish between a mother heartbeat and the fetal heartbeat, especialy at the early stages of a pregnancy.
Originally intended for use by health care professionals, this device is becoming very popular for home use.
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