"The first time we heard the heartbeat, I thought something was wrong like my baby was having a heart attack or something. It was so fast."
"My doctor explained that it was completely normal for it to sound like galloping horses and that it wasn't hurting my baby in any way."
The speed of a fetal heart rate often surprises new parents when it first becomes detectable by a baby Doppler. At about 9 weeks of age, a normal fetal heart rate will peak at an average of 175 beats per minute (BPM), which is around twice as fast as that of his or her mother’s. From then it decelerates to around 150 BPM for the middle term of the pregnancy.
Abnormal Fetal Heart Rate
An abnormal fetal heart rate early on in the pregnancy can be an indication of fetal distress, abnormal fetal development, or an imminent miscarriage. This may be caused by heart problems, a compressed umbilical cord, or an insufficient fetal oxygen supply. An improper fetal position can also lead to abnormalities in fetal heart rate.
Should your baby have a slow or irregular heart rate, your doctor or physician will frequently and intensely monitor the fetus. In some cases, the doctor may perform internal fetal monitoring, which involves attaching an electrode directly to the baby’s head through the cervical opening.
Natural Variations in Heart Rate
It is perfectly normal for your baby’s heart rate to naturally fluctuate, just as an adult’s does. Day to day activities including movement or sleep can cause variations in the BPM. During check ups, your doctor may even stimulate fetal movement to see if heart rate slightly increases immediately, as this is a sign that the fetus is developing normally.
The normal heart rate of a fetus from when it begins to beat (around 5 weeks), to the end of the first trimester, will increase, then decrease steadily over this period, as mapped out in the table below:
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Fetal Age
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Normal Fetal Heart Rate
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5 weeks
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Begins at 80 BPM, ends at 103 BPM
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6 weeks
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Begins at 103 BPM, ends at 126 BPM
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7 weeks
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Begins at 126 BPM, ends at 149 BPM
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8 weeks
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Begins at 149 BPM, ends at 172 BPM
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9 weeks
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155-195 BPM, average 175 BPM
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10-14 weeks
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120-180 BPM, average 150 BPM
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15-20 weeks
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140 BPM with 5-15 BPM variation
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21 weeks - Term
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130 BPM with 5-15 BPM variation
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Little Martin’s Drawer’s upcoming product, a handheld digital fetal Doppler, is designed to be used in the comfort of your own home, providing a safe way to listen to the sounds of your unborn child. This is also a great way to develop a bond and feel close to your baby, but please note that its use should not substitute regular prenatal care by a doctor or medical practitioner.
