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A prenatal monitor is a device used to detect a baby's heart rate while still in his mother's womb; it also can be used to monitor labor contractions. There are a several types of devices that are used to amplify the sound waves produced by the baby's heartbeat. Fetal monitoring is usually done during regular checkups by an obstetrician, but some women who have high-risk pregnancies may use a home monitoring system to check on the baby’s heart rate on a regular basis.
A prenatal monitor is very important during contractions, as it shows if the baby is under any stress and may signal complications. During labor, the heartbeat is detected using an electronic monitor, a device that wraps two belts around the woman’s stomach to monitor both the baby’s heartbeat and the mother’s contractions. There is also an internal version of an electric monitor.
A telemetry device is another type of prenatal monitor that is very similar to an electric monitor. This device, however, sends recordings of the baby’s heartbeat to the medical staff from a wireless transmitter that is attached to the mother's leg. This type of device isn't available at every hospital, but when it's available it can make monitoring a bit easier.
The Doppler instrument is used by most physicians and is the most recognizable type of prenatal monitor. After gel is applied, the Doppler instrument is placed on the woman’s abdomen and is adjusted until the physician catches the right spot above the uterus in which to hear the baby's heartbeat. By about the 12th week of pregnancy, the baby’s heartbeat can be detected, and the physician will either count the beats per minute or a readout of the data will be examined for any abnormalities. By the 18th week of pregnancy, the heartbeat can be detected by a fetoscope, a special type of stethoscope that doesn't require an amplifying device.
Home fetal monitoring devices have become popular, as many women find that listening to their baby's heartbeat is not only soothing, but also reassuring, especially for a woman who has a high-risk pregnancy or has experienced a miscarriage. Some high-level home monitors need to be requested by a physician, but there are many devices that can be purchased or rented. They are usually battery-operated, handheld devices that provide a digital reading of the number of heartbeats per minute. Many devices have additional features that allow the woman to record the heartbeat and create a digital copy or burn a CD of the recording. Families should make sure the prenatal monitor they purchase or rent is approved by an accredited health organization and is safe for consistent use during pregnancy.