At how many weeks is the baby’s heart beating during pregnancy? All about the fetal heartbeat

The fetal heart starts beating after only 5 weeks of pregnancy. However, it usually takes up to 9-10 weeks to hear it during the ultrasound.

Hearing your baby’s heartbeat for the first time is one of the most intense emotions of all sweet anticipation.

Also for this reason, the first ultrasound represents a unique moment, which one awaits with great trepidation. We can say that the fetal heartbeat is one of the most reassuring noises that exist. A sound, a flickering monitor that means life.

When does the fetal heart start beating?

The heart of the embryo begins to form very early during gestation and often even before the expectant mother realizes she is pregnant.

At 4 weeks of pregnancy (starting counting from the first day of the last menstruation),  a distinct and special blood vessel has already formed within the embryo , which will give rise to the heart and circulatory system .

Once formed, the fetal heart begins to beat spontaneously within 5 weeks (ie at the beginning of the second month of pregnancy). At this stage, however, it is too early to be able to feel it.

At how many weeks can you hear the heartbeat of the fetus?

Although the heart muscle begins to contract rhythmically at 5 weeks of pregnancy, the fetal heartbeat is only visible on ultrasound at around 6 weeks .

Generally, however, it takes until 9-10 weeks of pregnancy to feel the heartbeat for the first time , although the precise moment can vary slightly.

In this regard, it is important to underline that the current recommendations for gynecologists and obstetricians invite you to wait until the  10th week of pregnancy  before listening to the fetal heartbeat.

Fetal heart rate chart: how does the rate vary during pregnancy?

Many mothers report that the baby’s little heart in the belly has the sound of a galloping horse : in fact, being so small, it must beat faster than an adult’s to pump an adequate amount of blood.

In the early stages of development, the average fetal heart rate is very rapid and progressively increases to approximately:

• 110 bpm between 5-6 weeks
• 170 bpm within 9-10 weeks

In the following phases, however, the frequency decreases and drops on average to about:

• 150 bpm within 14 weeks
• 140 bpm within 20 weeks
• 130 bpm at the end of pregnancy

Although the heart rate is generally regular in the healthy fetus , a variation from beat to beat of about 5 to 15 beats per minute can be allowed.

Fetal heart rate chart: male or female?

It is popular belief that it is possible to find out if you are expecting a boy or a girl based on the heart rate of the fetus. If the heart beats at less than 140 beats per minute it would be a boy , while a faster heartbeat would indicate that a girl is on the way .

Unfortunately, this is just a false myth : in reality there are no differences between the sexes in terms of fetal heart rate, as demonstrated by various studies.

In addition, the heart rate can vary not only according to the gestational age, but also according to the activity and emotional state of the expectant mother (for example, it can accelerate in case of physical effort or anxiety).

What instrument is used to listen to the fetal heartbeat?

The gynecologist or midwife checks the heartbeat of the fetus through transvaginal or abdominal ultrasound (depending on the week of pregnancy in which it is performed). To amplify the sound, they use a portable ultrasound device called a Doppler.

Can you hear the heartbeat of the fetus by placing your ear on the belly?

Listening to the baby’s little heart without the help of special instruments is only possible in an advanced stage of pregnancy.

In particular, from the 27th week onwards ^, the future dad should be able to feel the heartbeat of the fetus by placing his ear on his partner’s belly. 

Already around the 20th ^week of pregnancy , however, it is possible to hear the fetal heartbeat with the help of a simple obstetric stethoscope .

Fetal heartbeat apps and trackers

There are hundreds of mobile apps and fetal heart rate monitors on the market , allowing parents-to-be to feel the baby’s heartbeat from the comfort of their own homes . However, these tools have no medical value and therefore cannot replace periodic checks .

In addition, the quality of the devices can vary greatly from model to model, with the risk of an inaccurate reading of the heartbeat that could cause unnecessary worry or anxiety.

For these reasons, if you want to buy an app or a fetal heartbeat detector for home use, talk to your gynecologist or midwife first : you can discuss its actual usefulness and possible advantages together, and possibly evaluate the most suitable model .

Also remember that, if you are worried about the baby’s health, the safest option is to contact the professional who is following your pregnancy : in case of need, in fact, they can schedule an ultrasound and check that everything is going well .

When can’t you hear the fetal heartbeat?

It may happen that the fetal heartbeat is not visible during the first ultrasound. The most common cause is that the ultrasound was done too early . This can happen, for example, when counting the weeks of pregnancy is inaccurate because conception occurred later than expected . For this reason, your obstetrician or midwife may recommend scheduling another ultrasound in 1 or 2 weeks.

If there is no heartbeat in a 7mm embryo , it could be a miscarriage . This eventuality will be ascertained with further ultrasounds after some time.

Heart ultrasound scans

Between the 7th ^and  13th ^week  of gestation, the first trimester ultrasound  is usually performed  , which is the first of the two recommended ultrasounds in pregnancy. This exam, in addition to providing valuable information on pregnancy (day of conception and expected date of delivery, single or twin pregnancy) will also check if the heart rate of the fetus is normal.

Subsequently, around the 20th week , the second recommended ultrasound is performed, which is called morphological . During this ultrasound, the gynecologist  will thoroughly check the structure of the baby’s heart .

Each year, about 9 out of 1,000 babies are born with a congenital heart defect , one of the most common and major birth defects. Although there are no drugs capable of treating heart disease in utero and some malformations can only be detected after birth, a diagnosis during pregnancy allows you to better plan care for the newborn. For example, you may decide to have your baby delivered in a facility where pediatric cardiac care is available immediately after delivery .

Sometimes the problem needs to be managed with surgery soon after birth , while other defects may need to be resolved later in life or treated with medication .

Usually, when the morphological ultrasound shows a possible cardiac anomaly, the gynecologist requests an echocardiography , a non-invasive examination which serves to evaluate the fetal heart in depth and which is usually performed between 18 and 24 weeks of pregnancy.

The good news is that most congenital heart defects can be cured and managed if discovered and treated early.  Children with congenital heart disease should have periodic checkups with a cardiologist in infancy and later.

The baby’s heart at birth

The heart and circulatory system of the newborn works very differently from the fetal one.

Before birth, the baby’s lungs are not yet functioning, as breathing begins only in the extrauterine environment. Until the baby is born and takes its first independent breaths, its circulatory system relies on the umbilical cord and placenta . The umbilical arteries and veins carry oxygen and nutrients from the mother’s blood to the fetus and release carbon dioxide and waste products.

For this reason, the fetal heart is characterized by some openings and communication channels (such as the foramen ovale and the ductus arteriosus of Botallo ) which are present only during intrauterine life.

As the baby begins to breathe after birth and the umbilical cord is cut, the fetal circulation system is turned off and the openings and ducts therein begin to close .

How to keep the fetal heart healthy

Most fetal development activities are beyond our control. Nonetheless, there are some good habits you can adopt to keep your baby’s heart as healthy as possible .

• Remember to take a folic acid supplement regularly , before and during pregnancy. In fact, this vitamin seems to play an important role in preventing congenital heart disease in children.
• Avoid alcohol and drugs.
• If you are a smoker, stop as soon as possible : maternal smoking during the first trimester is estimated  to be responsible for about 2% of all heart defects.
• If you have type 2 diabetes or  gestational diabetes , eat a proper diet and monitor your blood sugar during pregnancy, as diabetes is associated with an increased risk of fetal heart abnormalities.
• Not taking any medications without first consulting your doctor . In fact, some medicines can cause heart defects in the fetus.

Even if you have taken all possible precautions and followed all the doctor’s instructions, the baby could still be born with a congenital heart defect. It’s not your fault. There are many factors, mostly independent of our behavior, that can cause heart defects.

The good news is that, with early detection , your child can get the treatment they need to be able to live a healthy life.