The majority of fetal heartbeat detectors on the global market utilize continuous wave ultrasound, which means the signal is transmitted continuously. However, there are pulse wave detectors that operate similarly to radar. They first send a short transmitting pulse and then receive echoes from a specific area, filtering out loud signals from the skin and surrounding tissues (contact interference). Only a few companies have successfully developed devices using this complex working method.

Advantages of pulse wave fetal heartbeat detectors:

• Compact design (no cable attached to the probe, which is susceptible to damage)
• Small size and lightweight
• Ability to operate the device with one hand
• No contact interference

Ultrasound has been used in medical diagnostics since the 1960s. It is estimated that approximately 5 million pregnant women worldwide are examined daily using fetal heartbeat detectors. Within the intensity limits set by the American Institute of Ultrasound in Medicine (AIUM), there have been no known cases of harmful effects of ultrasound on the mother and the fetus. Our detectors emit ultrasound waves with significantly lower power compared to ultrasound scanners. The intensity of the ultrasound emitted by our wide-angle B7P2MHz probe is 20 times lower than the recommended standard.

Based on the feedback from users of our devices, it is possible to detect the fetal heartbeat as early as the 9th week of pregnancy. However, it should be noted that finding the heartbeat between the 9th and 12th week is a matter of chance. We recommend using a narrow-angle probe and headphones during this stage to avoid prolonged searching and potential stress for the pregnant woman. Typically, from the 12th week onwards, the fetal heart can be detected, and it becomes easier to locate it from the 15th week onward.

Our devices are available with two types of probes: a narrow-angle BP2MHz probe and a wide-angle 7-element B7P2MHz probe. We usually recommend the more affordable narrow-angle probe. However, in cases where convenience of use or the time spent searching for the heartbeat is critical, we recommend the wide-angle probe.

The BP2MHz probe has a smaller field of view. It requires more precise positioning over the fetal heart, which can take some time. In the early stages of pregnancy, the small field of view has an advantage as it collects fewer strong interfering signals from the mother’s vessels, making the weaker signals from the fetal heart more detectable.

The wide-angle probe has a larger field of view, and finding the fetal heartbeat is usually immediate, especially in later stages of pregnancy. Users of the B7P2MHz probe in hospitals, accustomed to convenient heartbeat detection, often acquire detectors equipped with this probe, such as the UDT-20SD and UDT-300SD, for their own clinics.

The fetal heartbeat detectors from the UDT-300 series have interchangeable probes, allowing for optimal adaptation to the stage of pregnancy.

During the process of touching the abdomen and moving the probe, strong and loud signals may appear, causing concern for the pregnant woman, and if headphones are used, they can momentarily deafen the operator. In our fetal heartbeat detectors, we employ automatic attenuation of strong signals, and in the case of the FD-10D, contact interferences are eliminated.

If unusual sounds occur, it is recommended to check the fetal heartbeat detector in a different environment.

Interference can arise from nearby operating devices or a faulty power supply. It is also possible that the probe or probe cable is damaged. In any case, you can contact BRAEL’s service center for advice or send the fetal heartbeat detector for repair. The repair process usually takes 2-3 days. Please provide a detailed description of the observed issues. During the repair, a thorough inspection of the device’s functions will be conducted, ensuring its performance is restored to that of a new detector.