Why is there no fetal heart?

1. The process of forming the fetal heart The process of forming the fetal heart is considered an important milestone for the normal development of the fetus. In it, the fertilized egg will form a zygote. The zygote will move down to the uterus, develop into an embryo, then attach to the uterus to implant. Along with that, the division process also takes place rapidly and the fetus begins to form. During pregnancy, the concentration of Hcg hormone secreted is large and appears in the urine. Therefore, pregnant women using a pregnancy test will show two lines - one of the first signs of pregnancy.
During fetal development, the fetal heart is the earliest formed organ. Accordingly, the fetal heart begins to form clearly and has a beat about 22 days after conception. At this stage, the primitive cardiac duct formed from the mesenteric mesenchyme begins to beat. This is followed by growth and curvature of the heart tubes, septum, and division of the heart into four chambers. So, in most cases, the fetal heart rate forms and appears before the mother realizes she is pregnant.
Ultrasound detection of the fetal heart or auscultation of the fetal heart is determined based on the activity of the heart, through real-time 2D images of the mother's uterus. The time of ultrasound to determine fetal heart usually falls between 5 weeks 3 days and 6 weeks 3 days of the fetus (fetal age is calculated according to the last menstrual period).
The fetus after 6 weeks of age can detect the color Doppler signal of the blood flow in the major vessels of the fetal body as well as the beating blood flow in the fetal heart. From the 20th week onwards, the fetal heartbeat becomes stronger and can be heard with normal headphones. The clearer the heartbeat sounds, the better the fetus is developing and healthy.
Based on the time of fetal heart formation and fetal development, the fetal heart can be detected by ultrasound from the 6th week of pregnancy onwards. In some cases, due to the incorrect calculation of the menstrual period, the gestational age may be later than expected, starting from the 8th week of pregnancy.
See now: Is it okay to have a fetal ultrasound without a fetal heart?

2. Why is there no fetal heart? Fetal ultrasound at 6 weeks shows a complete embryo, a fetal heart begins to appear, a sign that the fetus is developing very well. After this unstable initial period, the fetus will develop rapidly and steadily.
“What is no fetal heart rate and in many cases why is there no fetal heart rate on ultrasound or no fetal heartbeat can be heard even though the gestational age is full?”. Accordingly, some causes leading to the absence of fetal heart are as follows:
2.1. There is no fetal heart due to too early ultrasound Many cases of pregnant women taking the test have 2 lines, but fetal ultrasound at 6-7 weeks still does not show fetal heart. One of the reasons for the above situation may be due to incorrect gestational age. By determining the gestational age depends on many factors such as the last day of the menstrual period, the day of ovulation ... making the gestational age may be biased up to 2 weeks. In this case, an early ultrasound does not show a fetal heart and the doctor will schedule an ultrasound appointment for the mother 1-2 weeks later.
2.2. No fetal heart due to miscarriage One of the indispensable factors when answering the question of why there is no fetal heart at full week is miscarriage. Since after the 8th week, the ultrasound does not show the fetal heart, the doctors may suspect that the mother has had a miscarriage, asking for a detailed examination at this time is extremely necessary.
There are many causes of miscarriage as follows:
Miscarriage of unknown cause. The fetus is lost while the mother's health is completely healthy and stable; Health problems of pregnant women such as polycystic ovaries, anomalies related to the thyroid gland, cervix, blood clotting disorders ... increase the risk of miscarriage. In addition, some diseases caused by viruses such as measles, rubella, mumps, hepatitis B... are also one of the causes of miscarriage in pregnant women; Pregnant women have an injury or bump in the abdomen; Pregnant women suffer from stress and depression for a long time; Pregnant women are exposed to toxic environments or have a habit of using stimulants and alcohol.

2.3. Other causes Some other causes for the absence of fetal heart are as follows:
Inappropriate ultrasound method or faulty equipment: This is one of the common reasons why the ultrasound does not work. show fetal heart rate. Because to hear the fetal heart requires a stethoscope to reach the standard and a device with high sensitivity. In many cases, faulty ultrasound equipment will not hear the fetal heart or the fetal heart rate is very weak. Besides, ultrasound method also plays an important role, in the early stages of pregnancy, abdominal ultrasound will be difficult to detect fetal heart. Therefore, doctors often conduct transducer ultrasound to achieve the most accurate ultrasound results; Fetal arrhythmia: This cause is rare, but it can happen. Fetal arrhythmias usually only occur during a certain time of pregnancy and are temporary. Fetal arrhythmias can cause the fetal heart rate to rise to 160 beats per minute, then suddenly stop and return to normal. In this case, the doctor will conduct a re-examination to detect abnormalities early.

3. What to do when there is no fetal heart Besides the question "why is there no fetal heart", "what to do when there is no fetal heart" is also a matter of much interest and attention. Accordingly, pregnant mothers need to pay attention to a number of issues as follows:
- In case a pregnant woman has an ultrasound before the 7th week of pregnancy, she should not be too worried. Because at this point it may be too early to determine the fetal heart rate. The doctor will have a more in-depth examination and schedule an appointment for an ultrasound after 1-2 weeks for pregnant women;
- In case the pregnant mother suddenly does not see the fetal heart, although she still hears the normal fetal heart before, it is accompanied by unusual symptoms such as loss of feeling of morning sickness, vaginal bleeding, abdominal pain .. pregnant mothers need to go to medical facilities to be checked as soon as possible;
- In case from 12 weeks onwards, the ultrasound results still do not show the fetal heart, the doctor will appoint the pregnant mother to perform intensive tests to have an accurate diagnosis. In the event of an unfortunate miscarriage, the mother needs to find out the cause to prevent future pregnancies. The doctor also uses safety measures to help get the pregnancy out safely. Besides, mothers should not be too sad but need to calm down and take appropriate care of their own health as follows:
Avoid stress, stress, grief... Instead, mothers should find jobs to help relax. relax and make yourself comfortable; Eat and drink enough, enough quality, do not carry within 3 months after miscarriage to help restore the cervix; Before planning to become pregnant, it is necessary to vaccinate and supplement with necessary nutrients and minerals such as folic acid, iron...; Build a reasonable rest and exercise regime. Why there is no fetal heart can be caused by many reasons. Therefore, to ensure the health of both mother and fetus, mothers should visit antenatal care regularly and seek the advice and support of doctors.
Psychological and physical changes during pregnancy are inevitable, but some are normal and some are warning signs of abnormalities. Currently, Vinmec International General Hospital offers a comprehensive maternity care program for pregnant women right from the first months of pregnancy with full antenatal check-ups, periodical 3D and 4D ultrasounds. along with routine tests to ensure that the mother is healthy and the fetus is developing comprehensively.
In addition to regular check-ups, pregnant women will also be advised on nutrition and exercise so that the mother can gain weight reasonably while the fetus still absorbs nutrients well. In addition, pregnant women will be consulted and checked for health under the close supervision of experienced and specialized obstetricians, helping mothers have more knowledge to protect their health during pregnancy. as well as minimizing complications affecting mother and child.