Fetal heart monitor: What are the different types?
Fetal heart monitor is a device that can detect and amplify the heart beats of the fetus and enable the listeners to count and monitor the rate of heart beats. There are many devices with varying degrees of convenience, technology and comfort. But, all are effective when it comes to detecting and monitoring the heart beats. It choice of the devices boils down to the comfort of the users, more than anything else. Listed below are the most common types of fetal heart monitor that is available in the market.
Pinard Horn: This non technical device was invented in the early 19th century by a Doctor and it has been commonly used since then. This device is a small and short unit consisting of a flat surface of medium circumference at one end and a conical protrusion that forms itself to resemble an elongated cup ending with the open side. The hollow of the conical cup gradually reduces in circumference and is minimal when it meets the stub end of the device. While usage, the flat end is placed on the mother’s abdomen and the hollow end is placed on the ear. The unit is moved around the abdomen till an amplified sound of the heart beat is heard.
Stethoscopes and Fetal stethoscopes: A regular stethoscope is a very efficient fetal heart monitor. In fact, practitioners prefer to use them to detect heart beat of the infant unless they see a special need to use other specialized units. For a regular person, using the stethoscope might not be an attractive option because it takes time to get used to them. The other option is a specialized fetal stethoscope. This device is similar in appearance to the regular one but is slightly modified at the business end. There is a bigger circumference flat end that is more effective in detecting fetal heart beats that are faint.
Fetal Dopplers: These are the most effective and efficient means of monitoring fetal heartbeats. The fetal Doppler beams ultrasound waves into the womb and the reflected waves are reabsorbed and analyzed. A stimulated replica of the heart beats is amplified and played back to the listeners. The fetal Doppler is very accurate and can also display the beats per minute on its screen for the benefit of the listeners. The advanced technology eliminates the possibilities of errors and increases the chances of detection and enhances the method of monitoring. It is also the easiest to use amongst all devices and can be bought or rented for personal use.
The different stages of fetal heart beat
Heart beat of the fetus starts approximately six to seven weeks after ovulation. The heart starts forming by that time along with the other body parts and starts beating immediately to start the blood circulation process. Even though the requirement of circulation in the still developing fetus is minimal, the heart starts its functioning process to not only test itself but also to prepare itself for the rigors and processes that it is deemed to do. Modern heart beat detection units like fetal Doppler are well equipped to detect and time the heart beats from an early stage onwards.
During the initial stages, the heart beats are irregular and uncoordinated. It is found that the beats often fluctuate and try to maintain the sequence of the mother. As the weeks progress the number of beats increase exponentially till it reaches a peak of more than double the number of the mother’s. After this period, the heart beats of the fetus reduce and stabilize the normal pattern. The entire process is attributed to the fetal heart’s orientation towards its function and testing its own ability. The orientation pattern can also vary with different fetuses. It is also said that the gender of the fetus can be determined at this early stage by calculating the number of heart beats but this remains scientifically unproven.
The general week wise pattern of the fetal heartbeat can be generalized into six periods. The first period starts from the fifth week. The heart beat is irregular and can range between 80 to 100 beats per minute. In the second period of sixth week, the beats range from 101 to 125 BPM. The third period of seventh week will see an increase of up to 149 BPM and will further increase to around 170 BPM in the next week. The heart beats reach a peak of about 195 BPM in the fifth period or the ninth week of pregnancy. As the weeks progress, the rate of the beat gradually comes down and by the end of the twelfth week, they are more or less stabilized and range from 120 to 160 BPM.
Modern heart beat detectors like fetal Doppler can accurately stimulate the heart beat of the fetus and can detect beats as early as the sixth week. These units are available for general usage via sales or rentals. They can help parents to enjoy listening to the fetus’s heart beats, at the same time enabling them to track and monitor the progress.
Fetal heart rate and Gender predictions
Fetal heart rate and gender predictions are being done as early as 9 weeks of fetal growth. All of these predictions are not based on scientific practices but on heresy and misconceptions. It is said that the gender of the fetus can be accurately predicted by calculating the beats per minute of the fetus. If the BPM is higher than 140, then the fetus is supposed to be a female and if it is less than 140, it is supposed to be a male. There have been scientific experiments done about this theory and it has been conclusively proved that there is no relation between the heart rate and gender of the fetus. The best way to monitor heart rate is via a fetal Doppler unit.
Fetal Doppler uses ultrasound technology to stimulate the heart beat of the fetus. It also projects this sound electronically, which can be heard by surrounding people. There is a probe that emits ultrasonic waves into the womb. The returning waves are picked up by the probe and passed on to the body of the machine. The waves are then analyzed and heart beat is stimulated and outputted acoustically. The fetal Doppler is generally used by medical practitioners but its usage is becoming prevalent in the public world too. Many parents want to experience the thrill of listening to their offspring’s heart beats many times and that too from the comforts of their homes. As a result, sales of fetal Dopplers and also their rental numbers have been consistently shooting up.
The gender of the fetus can be accurately determined during the second trimester of the pregnancy. During the first three months, the embryo and fetus are in a formative stage and will be undergoing the process of development of internal organs like lungs, digestive system, heart, etc. It is highly unlikely to have visible indications of gender at this stage. So, predicting the gender of the fetus at this early stage becomes impossible. It is only after 12 weeks that the fetus starts developing genitals. Even these are visible after 16 weeks or so. After 16 weeks, there is no need to rely on unconfirmed predictions; the baby’s gender can be accurately determined by their genitals which are visible. There is no relationship between a fetus’s heart beat and gender. Each has to be determined separately and accurately.
