Fetal heartbeat: normal values, how and when you hear it

The fetal heart rate changes throughout the pregnancy, it is fastest during the 9th week and then decreases after the 13th, but throughout the gestation it remains faster than what the newborn’s heart rate will be. [¹] After hearing the fetal heartbeat for the first time, but not only, you may wonder which fetal heart rate is normal and which is not.

“Normal” Fetal Heart Rate

Most doctors define a fetal heart rate between 110 and 170 beats per minute (bpm) as “normal.” [1]

The initial rise – with a peak at the 9th week of pregnancy – coincides with the morphological development of the heart, and the subsequent decline could be the consequence of the functional development of the parasympathetic nervous system.

During labor, a typical fetal heart rate can range from 110 to 160 beats per minute, although brief variations outside this range can occur for a variety of (often perfectly normal) reasons. [2]

Fetal arrhythmia

A fetal arrhythmia can be:

  • a tachycardia (a fast heart rhythm)
  • bradycardia (a slower-than-normal heart rhythm)
  • an ectopic beat (an irregular rhythm)

Fetal arrhythmia occurs in only 1-2% of pregnancies and is considered a benign condition. Most of the time the problem resolves itself.

The underlying causes of an irregular fetal heartbeat include:

  • High consumption of caffeine and nicotine
  • Structural changes of the fetus in the second trimester (leading to mild and temporary irregularities)
  • Congenital heart defects

If a problem of this type is found, it is necessary to constantly monitor the state of health without underestimating or even dramatizing it.

The first contractions (in the embryonic period)

Around the 20th day of embryonic development, groups of mesodermal cells detached from the splanchnopleura organize themselves to form the endocardial tubes which, in turn, make contact with the primitive blood vessels. About two or three days later the cardiac tubes fuse along their entire length and the myoepericardium and the pericardial cavity wrap around them: this is a first sketch of the heart on which – between the 22nd and 23rd day – the first irregular contractions are already observed. We are talking about a sketch less than 1 mm long and therefore contractions not detectable during a normal medical examination.

When and how does the heartbeat feel?

You may be able to observe the heartbeat of the fetus for the first time at the first transvaginal ultrasound examination – around the 6th week, or – in the following weeks – with a morphological ultrasound examination.

Later in pregnancy – and particularly after the 30th week – the heart rate of the fetus can also be assessed with cardiotocography (CTG).

In doppler fetali

Finally, there are fetal dopplers, portable instruments – both professional and non-professional – which in some cases already at the 12th week can allow you to listen to the heartbeat of the fetus. But the usefulness and usability of these Dopplers depends on several factors, including the position of your uterus, the shape of your belly and how full (or empty) your bladder is, etc.

In short, fetal Dopplers, especially domestic ones, used without the supervision of a doctor, must be used with due caution and in the event of doubts or readings other than those expected, it is important to contact your specialist before worrying.


When you first hear the heartbeat of the fetus you may be concerned because it is quite different from that of an adult, but you should rest assured that it is most likely normal. If you are worried, ask for advice and trust only the findings and judgments of the specialist

Katherine Johnson, M.D., is a board-certified obstetrician-gynecologist with clinical expertise in general obstetrics and gynecology, family planning, women’s health, and gynecology.

She is affiliated with the Obstetrics and Gynecology division at an undisclosed healthcare institution and the online platform, Maternicity.com.

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