At the time of pregnancy, the main indicator of the life of the fetus is the heartbeat. When ailments appear, the rhythm instantly changes, signaling the occurrence of problems. That is why doctors are trying throughout the term to carefully monitor the dynamics of the heartbeat. With the approach of childbirth, the indicator will gradually change.
First heartbeats
Indications of the frequency of strokes are a fundamental characteristic of the normal course of pregnancy. Therefore, obstetricians so carefully monitor the fetal heart rate from the earliest possible date. It is worth noting that the development and final formation of the baby's vascular system continues until the last weeks of pregnancy.
Each mom wants to quickly hear the heartbeat of her baby, however, in the early stages, this will not work without special equipment. Only high-tech products (ultrasound, cardioscope) can detect the first arterial contractions. And then this procedure will give results only from the 5th week of pregnancy.
The embryo's heart-laying occurs at the end of the first obstetric month. Closer to the 5th week, the organ takes the form of a hollow tube. It was during this period that the first reductions appeared. You can study such a weak heartbeat only by ultrasound scanning (transvaginal probe). However, many gynecologists recommend doing the first ultrasound from the 7th week. At this time, the heartbeat is detected through a transabdominal sensor.
At home, the frequency of contractions with a stethoscope begins to be heard only at the end of the fifth obstetric month.
Weekly Heart Rate
You can investigate the frequency of contractions of the artery walls in the fetus at any stage of pregnancy after the first month until the onset of childbirth. However, this is not recommended until the 6th week, since the cardiac organ is still quite formed. Too frequent ultrasounds are also undesirable, as they harm the embryo. It is best to follow the schedule of scheduled examinations compiled by your doctor.
The fetal heart rate per week, starting from the 6th and ending with the 8th, will be 110-130 beats per minute. Moreover, the nature of the reductions may be different. Beats should be crisp and clear. A deaf rhythm may indicate the presence of a chronic or acute form of hypoxia.
The fetal heart rate for girls' weeks (throughout the entire third obstetric month) should be about 160-180 beats / min. In this case, the repetition of contractions should be through equal periods of time. This indicator is called rhythm. The fetal heart rate according to the weeks of boys in the third obstetric month should be in the range from 170 to 190 beats / min.
It is important that during this period, the frequency of reductions be normal. In the first trimester, babies are often diagnosed with heart abnormalities. If the frequency of contractions is above 200 beats / min., Then we can talk about the presence of tachycardia. If the heartbeat is less than 100 beats / min., Then we will talk about failure. Both diseases are a sign of embryo pathology and require special treatment.
The fetal heart rate by weeks (from the 13th to the time of birth) should be from 140 to 160 beats / min. This rate indicator is the same for boys and girls. It is worth knowing that in the second trimester the occurrence of arrhythmia is possible. This disease is characteristic of a fetus with oxygen deficiency or congenital heart defects.
Control Methods: Listening
The simplest and most common way to determine the heart rate, starting from the 20th week of pregnancy, is auscultation. This procedure allows you to listen to contractions through a stethoscope.
At this time, the fetal heart rate by week will already be noted in the form of double rhythmic beats. During auscultation, doctors also determine the nature of the contractions (deaf or clear). The norm of the heartbeat while listening to a stethoscope will be 40-60 beats in 20 seconds.
Starting from the 24th week of pregnancy, auscultation is possible in any part of the uterus. During childbirth, auditions are held every 15 minutes.
Ultrasound scan
The first ultrasound examinations are allowed from the 6th week, however, a scheduled examination is carried out only at the end of the second obstetric month. At such an early date, the doctor can determine the presence of contractions and their approximate frequency.
Fetal heart rate by week with ultrasound:
- from 110 to 135 bpm. (second obstetric month);
- from 165 to 185 bpm. (third obstetric month);
- from 140 to 165 bpm. (from the beginning of the second trimester).
Ultrasound scanning is the most accurate way to determine
heart rate and detect pathology.
Control Methods: Cardiography
This type of heart rate study is carried out only from the 28th week of pregnancy. It is worth noting that for the entire period the cardiography procedure is allowed only once. Its repeated carrying out is shown only at a late gestosis, a small or polyhydramnios, an infectious disease, a scar on a uterus, an early aging of a placenta. In these cases, the fetal heartbeat is heard for weeks in dynamics.
The procedure takes from 40 to 60 minutes. After that, the doctor evaluates the study. The normal frequency for cardiography is 135-165 bpm. Measurements are taken in a calm and active state of the fetus.
Echocardiography
Fetal heart rate by weeks of pregnancy can also be examined using a special ultrasound scanner that determines not only the frequency of contractions, but also the structural features of blood vessels and blood flow. This procedure is called echocardiography. It will be most indicative throughout the entire second trimester.
Diagnosis with an echocardioscope is prescribed in the presence of heart defects, with an infectious disease, with mother’s diabetes, with late pregnancy (after 38 years), and with suspected
fetal growth retardation.During the procedure, several types of scanning are used at once: one- and two-dimensional ultrasound, as well as Doppler mode. The norm of the frequency of contractions in echocardiography will be 140-160 beats / min.
Heartbeat detector
Instruments of this type of ultrasound are absolutely safe for mother and baby. In addition, they are very convenient to use in a hospital and even at home. Detectors not only determine the frequency of contractions, but also “visually” demonstrate their nature.
During the procedure, you can listen to the fetal heartbeat (starting from the end of the first trimester). This has a calming effect on mom, therefore, normalizes the child’s psycho-emotional state. The fetal heart rate by week, determined by the detector, should be in the range from 130 to 175 beats / min. The duration of one diagnosis is 8-10 minutes.
Listening to the fetal heartbeat by weeks, it should be remembered that the indicators should not have deviations from the norm for more than 20 beats / min. If this is observed, then this indicates the presence of pathology.
The number of examination procedures with an ultrasonic detector throughout the entire gestation period can reach up to 5-6 times.