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Listening to Your Baby's Heart at Home

If you are like the majority of expectant parents and couples, you will get a thrill out of hearing the heartbeat of your child to be for the first time.

Even if you are fortunate enough to have already seen the embryo or fetus of your future child through an ultrasound in the hospital, there is still something unmistakably exciting about getting to hear the steady, rapid beating of your baby's heart that brings home the fact that you are going to be bringing a baby home in about six months. This guide will provide information about when you can expect to hear your baby's heart beating starting from the 10th week of pregnancy and what the different sounds you hear may mean.

The Heart of The Fetus

The heart of the embryo or fetus will begin to beat approximately 22 days after conception occurs; this is typically around five weeks after the last menstrual period has occurred. By convention, this is referred to the fifth week of pregnancy. At this stage of development, the heart will be too small to hear, even if you listen with devices designed to amplify the fetal heartbeat. However, sometimes you can see the beating heart as a slight flickering in the chest when you observe the fetus through an ultrasound from as early as four weeks after the fetus is conceived.

Listening With A Doppler Instrument

Once you've passed the ninth or tenth week, it becomes possible to hear your baby's heartbeat when you go in for your prenatal appointment. The obstetrician or gynecologist you see will probably use a Doppler instrument to allow you to hear the heartbeat. A Doppler instrument works by bouncing sound waves, which are harmless, off the heart of the fetus. This is similar to how an ultrasound bounces sound waves off the entire baby to provide you with a picture of the baby. The angles at which the sound returns from the fetus vary in proportion to the ways in which the fetus moves.

As a result, a heart that is beating will affect the pattern of the returning sound waves, and the Doppler receiver collects those changes which are then interpreted by the computer to produce the sound of the heartbeat. Luck will play a significant role in your ability to hear the heartbeat at nine or ten weeks; the instrument will have to be located at precisely the right angle, and the position of your uterus will also affect whether you obtain results this early or not, as will your body mass distribution. Typically, the heartbeat is consistently identifiable once you pass twelve weeks when using a Doppler instrument to amplify the sound.

Interpreting The Fetal Heart Rate

While the precise heart rate will, of course, vary from one fetus to the next, the normal heart rate of a fetus around this time in the pregnancy is typically between 120 and 160 beats every minute. Although a lot of rumors abound about the topic, there aren't any differences between the heart rates of girls and boys, so you will not be able to determine the gender of your baby and start buying baby clothes simply by knowing if the heart beat is slightly faster or slightly slower.

You also will not be able to tell anything by how loud or quiet the heartbeat is; this is dependent completely on the volume controls of the Doppler instrument, as well as the angle and distance of the instrument to the heart of the fetus. There is no cause for worry if it does not seem to be particularly loud. If you are having twins, you might have a hard time distinguishing the heartbeats of each fetus, particularly if they sound similar. You can use ultrasound to view their hearts.

Last Updated: September 05, 2017