Fruit heartbeat by weeks: Features and norms in the table

A baby’s heartbeat becomes one of the most significant indicators of development as early as the first few weeks of pregnancy. Doctors and parents can learn a lot about the baby’s health from this sound, which is more than just a rhythm. Heart rate fluctuates in various ways from the beginning of pregnancy to delivery, so knowing what’s typical can be very reassuring.

Weekly heartbeat tracking can help make sure everything is moving in the right direction. Hearing that first heartbeat is an emotional and memorable experience for many expectant parents. Even though it’s thrilling, it’s crucial to understand the significance of the numbers and how the baby’s growth is reflected in them.

We will examine the evolution of the fetal heart rate in this article. We’ll go over the main characteristics of the heartbeat during pregnancy and offer a straightforward table that shows the average heart rate for every week.

Week of Pregnancy	Fetal Heartbeat (Beats per Minute)
6-7 weeks	90-110 bpm
8-9 weeks	130-170 bpm
10-12 weeks	160-180 bpm
13-16 weeks	140-160 bpm
17-20 weeks	130-150 bpm
21+ weeks	120-140 bpm

How the heart is formed?

The baby"s heart is one of the first to begin to form. A woman does not yet know that she is pregnant, but the baby is already undergoing intensive processes of organogenesis of the heart and great vessels. This process begins in the second week of pregnancy (from the date of conception). In the first week of its existence, the embryo forms two cardiac rudiments – endocardial tubes. They gradually merge into one, but two-layer. The most rapid growth of the tube occurs in the 3rd week of pregnancy (the first week from the beginning of the delay of menstruation). Despite its miniature size, the embryo"s cardiac tube has a rather complex structure: it has five sections, from which the atrium, ventricle, venous sinus will form, there is an arterial bulb and trunk. The baby"s heart acquires its characteristic appearance in the 5th week from the day of conception, That is, at 7 obstetric week. By this time, the heart is already divided into right and left halves, separated by two partitions.

It is interesting to note that the cervical region is where the heart forms, not the usual location for this organ. The organ gradually descends to the future location of the chest as it develops. The heart flips over on the way there, with the parts that formed at the top ending up at the bottom.

Due to the complexity of this process, any disruptions may result in severe pathology. For instance, the heart may stay in the cervical region or fail to turn over, in which case its apex may be facing downward.

At the 4th week of embryonic development, the interventricular septum is formed, the organ is divided into 2 parts. At the 6th week of the baby"s development, an oval window is formed in the septum and the heart becomes three-chambered. At 7 weeks, it begins and by the end of 8 weeks ends the process of formation of another partition and the heart becomes four -chamber, such as each of us. The embryo"s heart begins to beat at the end of the 5th week of pregnancy, this can be recorded by ultrasound results. There are no other ways to hear the tiny heartbeat in the early stages. The period from 2 to 8 weeks of embryonic period (from 4 to 10 weeks of pregnancy) is critically important.

Any teratogenic factor has the potential to interfere with the development of the heart and blood vessels, leading to the development of defects that may become irreversible and even unfit for human life. A woman’s bad habits, an unfavorable environment, detrimental production factors, etc., can all have this kind of influence.

When and why is it measured?

From the end of the 5th week until the very moment of birth, the fetal heart rate is measured at each ultrasound examination. This is not a tribute to tradition, but an important characteristic of the baby"s condition at the time of the examination. At what frequency is the heart of the crumbs, in the ultrasound protocol is indicated by the abbreviation of heart rate – the heart rate. At different stages of pregnancy, additional methods of listening to the baby"s heart appear. Echocardiography can be performed from about the 18th obstetric week. Ultrasound with Doppler and in color gives an idea not only of how correctly the heart is formed and how it beats, but also of how the blood circulates in the main vessels. From the middle of the second trimester, the method of auscultation is used – listening with an obstetric tube with a wide distal end (stethoscope). Every obstetrician-gynecologist has one in his office and usually every scheduled appointment with a pregnant woman begins with the listening procedure. This method does not allow calculating heart rate in numerical meaning, but gives an idea to the doctor how rhythmically and clearly knocks the child’s heart, and also to assume his presentation – if the heart of the heart is detected below the navel of the woman, they talk about the head presentation, when beating in the navel, to the right or to the left of it, they suggest the transverse arrangement of the crumbs, and if the knock of the heart is heard above the navel, with a high degree of probability the baby is in the pelvic presentation.

However, the method is not very accurate, especially when the placenta is positioned along the front wall, the mother is obese, the method is not accurate when the twins or triplets are pregnant, or the heart rhythms are poorly listened to.

Another technique called CTG (cardiotocography) is available starting at 30 weeks of pregnancy. It is designed to control all future mothers as well as to follow the signs. The technique is based on sensors registering two indicators: the fetus’s movements and heartbeat, which are both fixed, and the relationship between the movements and the heartbeat’s rapidity, which is characteristic. When a woman is giving birth, it is frequently necessary to attach the KTG apparatus sensors to her abdomen in order to record her heart rate and contractions. Thus, during childbirth, the fetus’s condition is tracked.

At home, a woman can hear the baby"s heartbeat in several ways, but all of them are intended solely to satisfy curiosity – hers and the future father"s. A woman needs special medical knowledge to understand what a particular change in the rhythm of the baby"s heartbeat means. We are not talking about situations when home heart rate monitoring is recommended by a doctor – in this case, special portable fetal monitors are used, which are given to the expectant mother for a while so that she can follow the doctor"s recommendation. An obstetric stethoscope can also be used for home listening – after 24 weeks of pregnancy, but this method is not available to the woman herself, since someone else will listen, for example, her husband. Today, fetal dopplers are available for sale – small devices with an ultrasound sensor. You can use it at home as early as 13-14 weeks of pregnancy.

Finding the listening point is the main challenge, and experience has shown that this does not always happen immediately. After 32 weeks of pregnancy, you can either use a standard phonendoscope or attempt to listen to the baby’s heartbeat through the abdominal wall with your ear; however, the baby needs to be comfortably positioned with their back to the abdominal wall.

Heart rate is an indicator about which doctors do not have a unified opinion. It is more often believed that it does not have high diagnostic accuracy, since there can be many reasons why the heartbeat can slow down or speed up, and even the mother"s usual anxiety or poor health will certainly affect the heart rate result. Why measure the heart rate then? Firstly, to diagnose the pregnancy itself – at 5 weeks. A small fertilized egg may be invisible in the uterine cavity, but its beating and characteristic sound will not allow the doctor to see the baby. Secondly, the baby"s heart muscle reacts to any changes in its condition, which can be important as part of a comprehensive assessment of the fetus"s condition. As an independent measure that allows you to make a diagnosis, measuring the heart rate does not act. But it advantageously complements the information that can be collected during ultrasound, laboratory tests.

However, taking the baby’s heart rate during delivery in a maternity hospital provides a clear picture of his health. The prognosis for a child experiencing acute hypoxia during labor is contingent upon the speed at which medical professionals identify the condition and determine the best course of action.

Norms

Before talking about heart rate norms, it is important to understand that during the formation of the cardiovascular system, the baby"s heart beats unevenly. After 8 weeks, the rhythm usually becomes more confident, clear. Much in this parameter is individual. If a woman suffers from toxicosis or has a cold or acute respiratory viral infection, the baby"s heartbeat always increases, and an examination during this period will give inflated indicators. If the mother lay on her back for a long time, as a result of which the vena cava was compressed by the pregnant uterus, then the heart rate may be reduced, but after a change in body position after a while it will return to normal. The baby in the womb sleeps and is awake, and in these two states it has a different heart rate. In the late stages of pregnancy, the baby is quite emotional, he hears a lot, feels, can be frightened, and the heart muscle first responds to this and gives high heart rate indications.

The tables show that there are differences in the norms for the early and late dates. Table of heart rate normative values – preliminary terms

Term, weeks.	Heart rate range (blows per minute)
5	80 – 103
6	101 -127
7	125 – 149
8	149 – 173
9	150 – 195
10	160-180
11	150 -180
12	148 – 177
13	145 – 173
14	146 – 169

Table of normative values ​​of heart rate – second half of pregnancy

Term, weeks.	Heart rate range (blows per minute)
15 – 32	130 – 160
32 – 38	140 – 160
38 – 42	120 – 160

Can these rules be regarded as strict? No, because the heart muscle of crumbs can be impacted by a plethora of factors. It is acceptable for the heart rate to vary slightly in either direction.

The doctor will undoubtedly recommend further testing if the heart rate data raise any doubts in his mind regarding the baby’s health and condition.

Deviations and causes

Nevertheless, women can’t help but feel afraid when they see the difference between the baby’s heartbeat and the typical norms. After learning from the doctor that the baby’s heart rate is abnormal, the expectant mother starts to worry, which makes matters worse because stress causes the female body to produce more adrenaline and cortisone, or stress hormones, which the baby’s heart muscle detects. So let’s examine the potential reasons for departures from the norm with composure.

Lower heart rate

It has been determined that your child has bradycardia. For the gestational age, the heart beats more slowly than it should. This typically occurs in the third and final trimester, when the baby starts to have cramps and the placenta starts to age and struggle to perform its nutritional and gas exchange duties.

A condition known as fetal bradycardia is defined as a heart rate that is 110 beats per minute or less. Please be aware that the heart rate may drop to these levels during CTG, but it will eventually rise back to its initial levels. Bradycardia is characterized by a continuous lowering of heart rate that is seen during the test.

Bradycardia itself does not indicate any specific disease, but doctors are very attentive to it, since it always indicates that the child"s condition is significantly impaired. Slow fetal heart rate can be heard if the woman leads an unhealthy lifestyle – smokes, drinks alcohol and uses drugs during pregnancy. Often, the baby"s heartbeat slows down due to the mother"s anemia (this is the reason why a decrease in heart rate is more often observed in the third trimester). If a woman has oligohydramnios or polyhydramnios, then the condition of the fetus may also be impaired. A violation of the amount of amniotic fluid is diagnosed quite easily, and such women are closely monitored throughout the pregnancy. The cause may be the woman taking drugs with a hypnotic effect, abuse of sedatives. Sometimes persistent bradycardia indicates congenital malformations.

A slow heart rate in a child is always an alarming sign, since it indicates that the baby is in a state of decompensation, that is, the disorder is already at least chronic, and the baby"s body no longer has the resources and ability to compensate for what it is not receiving. Bradycardia may indicate severe intrauterine chronic hypoxia (oxygen starvation), fetoplacental insufficiency, placental infarction, severe Rh-conflict in a Rh-negative woman with a Rh-positive child, mechanical asphyxia by the umbilical cord (entanglement around the neck). The response of doctors to bradycardia should be immediate. It is necessary to establish the cause that led to the condition as soon as possible and eliminate it. If it is not possible to establish or eliminate it, an early emergency caesarean section is performed to save the child"s life and in his interests. The only case when bradycardia is not an indication for urgent hospitalization is the detection of a slowdown in the heart rate due to a temporary circulatory disorder (compressed vena cava, umbilical cord compressed by the child inside the uterus). Usually, the woman is asked to walk around for half an hour, come back and undergo examination again. Physiologically conditioned bradycardia is not confirmed during a repeat examination.

The woman is admitted to the hospital if her heart rate readings drop once more because both she and the unborn child could need medical attention at any time.

Increased heart rate

Elevated fetal heart rate indicators are less dangerous than low ones. It has already been said that fear, stress may well be the cause of such examination results. But even if it is not a stress, often a beating heart is a sign that the baby is fighting, his condition is compensated. High heart rate values ​​are called tachycardia, they say about it if the heart rate exceeds 175 beats per minute. The deviation should also be stable, persistent. The exception is the period from 8 to 11 weeks of pregnancy, when a high heart rate is a physiologically determined norm. The reason for increasing frequency may be the bad habits of the mother, as well as some of her diseases. For example, with hyperfunction of the thyroid gland, when the level of its hormones increases, a change in the frequency of heart beating in both the baby and his mother may be observed. In the case of severe toxicosis, if vomiting for a woman becomes familiar, the likelihood of dehydration of the body increases, and in this case the baby’s heart is listened to with the definition of tachycardia. Fetal tachycardia may be caused by heart disease of the mother, disorders in the functioning of her kidneys.

The infant’s fast heartbeat could also be caused by internal factors, such as early hypoxia, structural placental abnormalities, or infections inside the uterus. If the child’s oxygen starvation started recently, the body perfectly compensates by making the adrenal glands function a little harder. They claim that once bradycardia sets in, the fetus’s condition has gotten worse because it has stopped fighting and making up for the oxygen shortage. During this period, the condition is compensated for by an increase in heart rate. It may perish if immediate medical attention is not given.

It should be mentioned that an abnormally fast heartbeat is another symptom of certain chromosomal disorders. For example, concurrent tachycardia is a common occurrence in fetuses with Down syndrome. However, listening to the heart alone is insufficient to diagnose chromosomal abnormalities; a specific set of diagnostic tests is required.

An exciting developmental milestone during pregnancy is the fetal heartbeat, which provides parents with a palpable link to their unborn child. The heart starts beating as early as six weeks into pregnancy, and tracking the heartbeat helps monitor the health and growth of the unborn child.

Heart rate norms are a crucial sign of a healthy pregnancy and vary by week. Doctors can make sure everything is going well by keeping an eye on these rates, and parents can feel more at ease knowing what’s normal at each stage.

Being aware of your baby’s pulse on a weekly basis can help you stay informed and at ease. It is always best to speak with your doctor if you have any concerns as they can offer the appropriate advice and assistance.

One of the earliest indicators of life during a pregnancy is a baby’s heartbeat, and monitoring its growth week by week can reveal vital information about the health of the unborn child. This article explains what’s normal and what may need special attention by breaking down the typical heart rate ranges for each stage of pregnancy. As the pregnancy goes on, the simple-to-understand table will provide parents with clarity and comfort as they track the progress of their unborn child’s heartbeat.

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