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Chronic intrauterine fetal hypoxia. Dangerous consequences of hypoxia during pregnancy. Causes of fetal hypoxia

Fetal hypoxia (“oxygen starvation”) b is not a specific disease, but a complex of changes in the body of the fetus due to its insufficient supply of oxygen, which has arisen due to pathological processes occurring in the body of the mother and fetus, as well as in the placenta. This syndrome is characterized by disturbances in vital organs and, above all, in the central nervous system.

Statistics show that fetal hypoxia occurs in 10.5% of pregnancies, and the syndrome can develop at different stages of intrauterine development of the child.

According to the rate of development of oxygen starvation, doctors classify the syndrome as follows:

  • Lightning or sharp: as a rule, it occurs within a few minutes or hours - during complications in childbirth (for example, with rapid or, conversely, prolonged labor, clamping of the umbilical cord or its prolapse, due to prolonged compression of the head in the birth canal).
  • Subacute: develops a day or two before birth.
  • Chronic: develops gradually with a moderate oxygen deficiency (the fetus can adapt to it) due to the incompatibility of the blood of the mother and child, as a result of toxicosis, infection of the fetus or prolonged pregnancy, etc.

Depending on the degree of oxygen deficiency in the fetus, different consequences can be observed, which will be discussed a little lower.

Why does hypoxia occur?

There can be several reasons for the occurrence of fetal hypoxia:

1. Maternal anemia- Decreased hemoglobin level. This disrupts the function of red blood cells - the delivery of oxygen to the tissues of the body.

2. The presence of congenital and acquired diseases and defects of the heart and myocardium(e.g. hypertension, heart disease), diseases of the lungs and respiratory system (e.g. chronic bronchitis, bronchial asthma), which can lead to insufficient activity of these organs and circulatory disorders. This, in turn, leads to a malfunction of the “mother-placenta-fetus” system, to the so-called placental insufficiency. In addition to diseases of the heart and respiratory system, the supply of oxygen to the blood can be affected by diabetes mellitus, kidney disease, multiple pregnancies, alcohol and/or drug addiction, and smoking.

3. Violations of the fetal-placental blood flow:

  • hemolytic disease - incompatibility of blood groups of the mother and fetus;
  • preeclampsia (severe late toxicosis);
  • placenta previa (full or partial overlap of the placenta exit from the uterine cavity - uterine os);
  • premature detachment of a normally located placenta;
  • cord entanglement;
  • pathology of the development of the placenta or umbilical cord;
  • congenital malformations of the fetus;
  • prolongation of pregnancy;
  • intrauterine infection or intoxication of the fetus.

4. Problems associated with labor:

  • anomalies (discoordination or weakness) of labor activity;
  • uterine rupture;
  • difficulties in the exit of the fetus from the birth canal due to its large size or incorrect position;
  • prolonged squeezing of the head in the birth canal during childbirth.

As you can see, there are enough reasons that can cause fetal hypoxia.

Symptoms of fetal hypoxia

At the initial stage of fetal hypoxia, its rapid, and then slowing of the heartbeat and muffled heart tones are observed. You can also observe the restless behavior of the fetus - its activation (increased motor activity). However, the activity of the child is manifested with a mild degree of oxygen starvation. With severe (prolonged or progressive) oxygen deficiency, the baby, on the contrary, moves more slowly and less frequently, the strength and frequency of his tremors are significantly reduced.

Situations when:

  • the baby moves no more than 3 times per hour;
  • the frequency of his heartbeat quickens and exceeds 160 or, conversely, decreases to 100-120 beats per minute;
  • muffled heart sounds.

How to determine fetal hypoxia

You can suspect fetal hypoxia by changing the active activity of the baby. However, only a doctor can confirm or refute your personal suspicions.

The following methods are used to diagnose fetal hypoxia in modern gynecology:

  1. obstetric ultrasound. Allows you to identify a delay in the development of the fetus, as well as the volume, color and composition of amniotic fluid.
  2. Cardiotocography. Allows you to track the heart rate of the fetus and its motor activity.
  3. Fetal phonocardiography. Tracks changes in the heartbeat at rest and during movement - they are used to judge the condition of the fetus.
  4. Dopplerometry of uteroplacental circulation. Allows you to study the speed and nature of blood flow in the vessels of the placenta and umbilical cord.
  5. Amnioscopy(this procedure is contraindicated in case of threatened miscarriage, colpitis, cervicitis and placenta previa) and amniocentesis. It is carried out through the cervical canal and allows you to visually determine the color, amount and transparency of amniotic fluid, as well as the presence of inclusions in them (meconium, flakes). This procedure allows you to make biochemical tests - to examine the content of hormones, enzymes, carbon dioxide concentration and measure pH. A direct assessment of amniotic fluid is made in the initial period of childbirth, after the outflow of fluids. If the liquid has a greenish color, and meconium is found in it, this indicates in favor of hypoxia.

The consequences of intrauterine fetal hypoxia

If fetal hypoxia develops in the early stages of pregnancy, for example, at 6-11 weeks, then a lack of oxygen leads, first of all, to a delay in the development of the fetal brain, to a violation in the structure and functioning of blood vessels, and the development of the heart, kidneys and intestines of the child suffers . There is a slowdown in the development of the embryo, which can cause various pathologies.

With severe, prolonged and progressive hypoxia and / or lack of oxygen in late pregnancy, not only the growth of the child is retarded, but also noticeable damage to the central nervous system, ischemia and necrosis in various organs. This, in turn, is fraught with a decrease in the adaptive abilities of the newborn (independent breathing after childbirth, the ability to suckle and digest food, maintain body temperature, etc.).

Changes in the vital organs of the fetus can cause asphyxia (observed in 75-80% of cases of hypoxia) and death before birth (intrauterine). Often in such cases, and intracranial birth trauma. All this after the birth of a child can lead to mental and mental disorders, cerebral palsy and neurological diseases.

Prevention of intrauterine fetal hypoxia

Prevention of intrauterine fetal hypoxia requires a responsible approach to pregnancy from the future mother and includes:

  • treatment of the organs of the reproductive system;
  • treatment of chronic diseases;
  • regular, rational and proper nutrition;
  • compliance with moderate physical activity: abandoning extreme sports in favor of activities that promote breathing training (for example, breathing exercises, aqua gymnastics and swimming, singing);
  • observance of the regime of rest and sleep, the rejection of frequent and abrupt changes in climate and time zones;
  • rejection of bad habits.

You need to prepare for conception in advance, and not “correct mistakes” by learning about the pregnancy that has already begun. In addition, it is necessary to register in a timely manner (up to 12 weeks) and regularly (in the first trimester once a month, in the second trimester - once every 2-3 weeks, in the third trimester - every 7-10 days) visit a doctor - obstetrician-gynecologist - for control examinations. At the same time, the attending physician will select the correct method of delivery, in which the likelihood of fetal hypoxia during childbirth will be minimized.

To prevent or treat fetal hypoxia, the doctor may prescribe medications: No-shpu or Euphyllin (expand the vessels of the uterus and fetal-placental section), Magne B-6 or Ginipral (relax the muscles of the uterus), Actovegin or Trental (normalize the rheological properties of blood in the system "mother - placenta - fetus").

This is not a complete list of drugs that a doctor can prescribe, because he selects them personally, depending on the indications and characteristics of the course of pregnancy.

If the fetus has suffered from hypoxia for a long time, then for a period of more than 28 weeks, the question of emergency delivery by caesarean section may arise.

Be healthy you and your kids!

Especially for- Elena Kichak

Fetal hypoxia is a fairly common diagnosis in pregnant women. Fortunately, it is not always confirmed. But doctors often play it safe, and women who are at risk of developing this pathology are taken under special control. To understand what the danger of oxygen deficiency is and how to avoid it, we will analyze what are the causes of fetal hypoxia, what is its essence, what are the symptoms, treatment and prevention.

What is hypoxia

The life of an adult is built in such a way that we ourselves get our own nutrients from food, and oxygen from the air we breathe. We have a functioning digestive system, respiratory system, as well as various organs perform an excretory function, freeing the body from waste products in a timely manner. In a fetus in the womb, all internal organs and systems are in the stage of formation and growth, and the body is provided with nutrients and oxygen through the bloodstream. Mother's blood, saturated with everything necessary, provides all the needs of a growing organism.

If this process is disturbed for some reason, starvation of the fetus begins, including oxygen. It is this cessation or slowing of the transfer of oxygen and nutrients to the child that is called hypoxia.

The development of hypoxia can be associated with a huge number of reasons and occurs both during pregnancy and during childbirth.

Causes and prevention of lack of oxygen

A woman can hear the diagnosis of "hypoxia" at about the 28th week of pregnancy, and sometimes even earlier. The factors due to which fetal hypoxia can develop during pregnancy include the state of health of the mother and her lifestyle. The risk of pathology arises if the mother has untreated infections of the genitourinary system, as well as exacerbated chronic diseases of the cardiovascular system, kidneys or breathing. Hormonal disorders in a woman's body also affect the development of hypoxia.

All these risks can be leveled by preparing for the birth of a child in advance. Before planning a pregnancy, it is necessary to undergo a comprehensive examination, treat infectious diseases and achieve a stable remission for chronic diseases. It is also highly desirable to check the state of the hormonal background and check the state of the thyroid gland. This is the initial prevention of fetal hypoxia and other equally severe pathologies.

If it was not possible to do this at the right time, it is important to consult a doctor as soon as possible and choose the methods suitable for pregnant women and the optimal terms of treatment. Treatment of most infections is carried out after the 12th week of pregnancy, when the formation of the main organs and systems of the fetus ends. After this period, the child is basically only growing, and the harm from medications will not be so global.

Hypoxia in newborns, as well as in those that have not yet been born, may develop due to an immunological conflict in blood group and Rh factor. If the mother is a carrier of negative Rh blood, and the child, for example, inherits a positive Rh from the father, then an Rh conflict may occur. This disorder rarely occurs in the first pregnancy. If a woman has already undergone childbirth or an abortion, then antibodies could remain in her body that will destroy the fetal immune system as foreign. This can be avoided by administering anti-Rhesus immunoglobulin immediately after childbirth (or abortion). Thus, we protect not already born baby, but make the next pregnancy safe.

Late toxicosis and the development of preeclampsia are factors that, with a very high degree of probability, cause fetal hypoxia. That is why in the second half of pregnancy it is so important to regularly visit a doctor and, if necessary, not refuse hospitalizations. Edema is a terrible symptom of preeclampsia, which is why doctors carefully monitor weight gain in expectant mothers. With gestosis, the blood flow is disturbed not only in the mother's body, but also in the mother-child system. Nutrients, and most importantly oxygen, are not delivered to the child in the right amount. It is known that nerve cells are the first to suffer from a lack of oxygen. Brain hypoxia begins to develop in newborns.

Doctors say that the physiological cause of hypoxia is the defective work of the placenta. Early aging of the placenta can be associated not only with medical factors, but also with the lifestyle of a pregnant woman.

The risk of hypoxia is primarily caused by physical and mental overload during pregnancy, insufficient quantity and quality of sleep and rest. Increases the risk of smoking and drinking alcohol.

But a sedentary lifestyle and excessive nutrition are no less dangerous than overload. If a woman moves too little, and being outdoors is reduced to sitting on a park bench, blood flow is slowed down. Only active physical activity can saturate the blood with oxygen, so necessary for the child.

Diagnosis, symptoms and treatment of hypoxia

To diagnose hypoxia, methods such as CTG, ultrasound and dopplerometry are used. The CTG procedure is a study showing the dependence of the fetal heart rate on its motor activity. Ultrasound gives an idea of ​​the condition and location of the fetus, and also shows the degree of maturity of the placenta and its performance. Doppler will help to assess the quality and strength of the blood flow that provides the baby with oxygen.

But the woman herself can and should monitor the condition of her child, notice the early symptoms of fetal hypoxia. She can do this already from 20 weeks of pregnancy, or even earlier, when she begins to feel movements. If their number has sharply decreased, less than 10 per day, there is every reason to consult a doctor and do an unscheduled ultrasound of the uterus.

In addition, the doctor himself monitors the condition of the child. At each appointment, he listens to the baby's heartbeat with a special tube - an obstetric stethoscope. It also measures the length of the uterus and the volume of the abdomen with a centimeter tape. If their growth is insufficient, ultrasound is also prescribed in order to ascertain the presence or absence of intrauterine growth retardation of the fetus.

When fetal hypoxia is detected, treatment is carried out immediately. If there is no acute oxygen deficiency, the doctor tries to find out the cause of the pathology. For example, if the problem is placental insufficiency, blood thinners may be prescribed, as well as drugs that relieve tension in the uterus.

The doctor decides how to treat fetal hypoxia. Each case is individual. However, it is often impossible to find out or eliminate the cause of the lack of oxygen, and then it remains only to carefully monitor the movements of the fetus for a woman, and doctors periodically perform studies of blood flow in the umbilical cord and heart rate in the child. In case of acute oxygen deficiency, a woman is urgently delivered by surgery.

Instruction

Try to breathe fresh air. If you live in a city, try walking early in the morning or late in the evening when there isn't much traffic on the streets. Try to periodically travel to the forest or out of town. Ventilate rooms regularly. Learn proper breathing techniques that will provide additional oxygen to the cells. Try not to wear clothing that can make breathing difficult.

Choose the appropriate type of physical activity, which is generally invaluable during. It can be yoga, Pilates, walking, water aerobics. Practice regularly and enjoy. In this case, after a few weeks you will notice an improvement in well-being, as well as provide yourself with hypoxia prevention, flexibility and good mood.

Talk to your doctor about prescribing antihypoxant medications. As a rule, doctors recommend some of them (for example, actovegin, instenon) as a preventive measure. Often, gynecologists also prescribe a course of oxygen cocktails, which are an excellent tool for the treatment and prevention of hypoxia. Remember that these cocktails are best taken in, or purchase a device for making them in. Similar drinks sold on the street or in shopping centers are not recommended for consumption due to the chemical additives they contain.

Brew tea from herbs that improve blood circulation: blackcurrant leaves, linden, lemon balm. The list of these plants is much longer, but not all of them are allowed to be taken during pregnancy. Such a drink will be delicious both hot (with honey, lemon,) and chilled (with ice cube, lime and fresh mint).

Useful advice

Regularly undergo the necessary examinations (ultrasound, dopplerography, biochemical blood test) to exclude circulatory disorders.

Sources:

  • how to avoid fetal hypoxia

hypoxia fetus- this is an insufficient supply of oxygen to the fetus, associated with diseases of the mother, disorders of the uteroplacental or umbilical blood flow, diseases of the child. Diagnosis of hypoxia is based on a direct assessment of the condition fetus and analysis of the results of indirect methods.

You will need

  • - observation of fetal movements;
  • - listening to the heartbeat with a stethoscope;
  • - cardiotocography;
  • - doplerometry;
  • - amnioscopy.

Instruction

If you notice changes in motor activity, this may be a sign. In the initial stage, you can detect the restless behavior of the child, expressed in the increase in frequency and intensification of his movements. With an acute lack of oxygen and an increase in hypoxia of movement fetus are starting to weaken.

Be sure to tell your doctor about changes in movements. He listens to the heartbeat with a stethoscope. fetus, evaluate the heart rate, rhythm, the presence of noise. But such a method can reveal only gross changes that often occur during acute hypoxia. The doctor may also suspect chronic hypoxia by indirect signs, such as a decrease in the height of the uterine fundus associated with growth retardation fetus, and oligohydramnios.

If you suspect hypoxia You will be given a cardiotocography (CTG). This study is successfully carried out in polyclinics. With the help of elastic straps, an ultrasonic sensor is attached to the abdomen, which is fixed in the place of listening to the heartbeat fetus. Diagnostic value is the frequency of increased and decreased heart rate. If an increase in heart rate is a response to movement fetus or contractions of the uterus (at least 5 in 30 minutes), then we can talk about a favorable condition fetus. To do this, a non-stress test is performed as part of the CTG, the essence of which is the appearance of an increase in heart rate in response to the movements of the child or uterine contractions. If the fetus does not give any reaction, this allows us to talk about hypoxia.

With the help of dopplerometry, a study of blood flow in the vessels of the uterus, umbilical cord and fetus. In the presence of circulatory disorders, it is possible to assess the severity of hypoxia and take measures for a further successful course

Many people know about the dangers and consequences of intrauterine fetal hypoxia, so the fear of hearing such a diagnosis is fully justified. Any expectant mother can panic, imagining that her baby does not have enough oxygen. But is it all that scary? What signs indicate fetal hypoxia and is it possible to prevent this phenomenon?

Fetal hypoxia and its forms

The baby during fetal development receives oxygen from the mother's blood through the placenta. If its intake is disturbed, then fetal hypoxia occurs, which negatively affects the formation and development of its organs and systems, as well as the general condition of the baby.

Quite often, oxygen starvation is associated with fetoplacental insufficiency - a phenomenon that characterizes the occurrence of disturbances in the structure and functioning of the placenta. As a result, feeding and breathing of the fetus is complicated.

A small short-term hypoxia is usually not dangerous for the fetus. But prolonged or acute lack of oxygen can lead to irreversible consequences.
Alcohol consumption leads to the development of chronic fetal hypoxia

Hypoxia can occur throughout pregnancy:

  • in the first months, oxygen starvation usually causes disturbances in the formation of important organs in the fetus (most often the nervous system);
  • in the later stages, the lack of oxygen also adversely affects the development of the baby and often leads to the need for a caesarean section long before the appointed date;
  • oxygen starvation can develop during childbirth. If hypoxia is prolonged, it poses a serious danger to the life and health of the child. In severe form, this is asphyxia, that is, strangulation of the fetus.

There are forms of hypoxia:

  • chronic - occurs with a prolonged lack of oxygen in the fetus. It can be provoked by severe toxicosis, impaired functioning of the placenta, smoking and alcohol consumption by the mother, etc. Hypoxia develops gradually, intensifying over time;
  • acute lack of oxygen occurs as a result of complications in late pregnancy and during childbirth. Oxygen starvation occurs abruptly and develops rapidly. Treatment is most often not possible. An urgent delivery is required.

Reasons for the development of pathology

The causes of chronic hypoxia include:

  • fetoplacental insufficiency (impaired functioning of the placenta);
  • intrauterine infections and fetal malformations;
  • multiple pregnancy;
  • smoking and drinking alcohol;
  • acute and chronic diseases of the internal organs of the mother;
  • low hemoglobin in a pregnant woman;
  • diabetes;
  • severe toxicosis;
  • experiencing stress;
  • abnormal presentation of the fetus.

 Cord entanglement can provoke acute fetal hypoxia

Acute hypoxia can lead to:

  • increased tone of the uterus;
  • placental abruption;
  • uterine rupture;
  • cord entanglement;
  • weak generic activity;
  • rapid birth.

Symptoms and Diagnosis

It is extremely difficult to detect hypoxia in the first months of pregnancy. Only a few objective factors (low hemoglobin, diabetes, smoking, etc.) can suggest its presence.

A reliable diagnosis can be made after 18 weeks of pregnancy, when the fetus begins to move in the uterus. The greatest suspicion is caused by a change in his motor activity, a rapid or slow heartbeat.

The expectant mother needs to pay attention to the following manifestations:

  • prolonged absence of baby movements;
  • increased activity of the fetus (frequent movements);
  • change in the nature of the motor activity of the child. For example, the movements were rare, and then suddenly became more frequent. Or, on the contrary, the baby was actively moving, and then suddenly stopped.

In all of these cases, you should immediately consult a doctor.
CTG is performed several times during the 3rd trimester of pregnancy and during childbirth

Diagnostic methods

Hypoxia is diagnosed using the following methods:

  • Ultrasound - performed after 18 weeks of pregnancy;
  • CTG (cardiotocography) - is carried out after 30 weeks of pregnancy and during childbirth and consists in recording and analyzing the heart rate of the fetus in motion, at rest, during contractions;
  • dopplerometry - is a type of ultrasound diagnostics and is carried out after 18 weeks of pregnancy in the direction of a doctor. The intensity of blood flow in the vessels of the fetus, uterus and placenta is assessed;
  • amnioscopy - is carried out in the later stages (after 37 weeks) by introducing a special device - an amnioscope - through the cervix. The method allows you to assess the state of amniotic fluid (quantity, color and the presence of impurities in them) and the fetal bladder.

Indicators that indicate oxygen deficiency:

  • the fetus is smaller in size and weight than the norm characteristic of a given gestational age, which indicates a developmental delay;
  • polyhydramnios or oligohydramnios;
  • violation of the fetal heartbeat;
  • violation of blood flow in the vessels of the uterus, placenta and umbilical cord;
  • the color of the amniotic fluid is green, it contains meconium (usually diagnosed during childbirth).

Consequences of oxygen starvation of the fetus

Acute hypoxia is more dangerous because it develops rapidly. In the absence of measures to eliminate it, with a high degree of probability, suffocation and death of the fetus may occur.

Other dangerous consequences of acute oxygen deficiency include:

  • death of nerve cells and pathological changes in the tissues of the brain, which leads to a lag in intellectual and speech development;
  • hemorrhage in various organs.

Consequences of chronic hypoxia:

  • miscarriage;
  • premature birth;
  • developmental delay before and after birth;
  • violation of the respiratory system of the baby;
  • diseases of the nervous system;
  • metabolic disorder in a child;
  • difficulties in adapting the newborn to living conditions.

Video: lecture on hypoxia and its consequences

Prediction of the consequences of oxygen starvation of a child

The consequences of hypoxia are diagnosed during childbirth using the Apgar scale. If the child's condition is estimated from 4 to 6 points in the first minute and 8 points or more - in the fifth minute, then this indicates an average severity of oxygen deficiency. Lower ratings can have severe consequences.

In the first years of life, the baby may appear:

  • hyperactivity;
  • neurological diseases;
  • lag in growth, weight and development of cognitive processes;
  • mental disorders, etc.

For treatment, special massage, physical education, and medications are prescribed. Most often, with careful observation and proper treatment, the health of the child improves during the first year of life.

How is hypoxia treated?

Depending on the degree and causes of hypoxia, treatment can be carried out both in a hospital and on an outpatient basis. Measures are being taken to improve blood circulation in the placenta, reduce the tone of the uterus, and enhance metabolic processes.

The expectant mother needs to make adjustments to her lifestyle:

  • reduce emotional stress and physical activity (less intensively engage in labor activity, take breaks more often);
  • daily for 2-3 hours to spend time in the fresh air;
  • it is recommended to do breathing exercises, yoga, water aerobics, swimming.

If the measures taken are ineffective and hypoxia persists, then early delivery is indicated (for a period of more than 28 weeks).

With prolonged hypoxia, medications are prescribed:

  • vitamins E, C, B6;
  • Eufillin;
  • Ginipral and others.

In a situation of acute oxygen deficiency, glucose, insulin, calcium gluconate, etc. are often administered, oxygen is inhaled using a mask.

Photo gallery: drugs for the treatment of oxygen deficiency in the fetus

Curantil is a drug used to improve blood circulation Actovegin is a drug with an antihypoxic effect that activates the delivery and absorption of oxygen and glucose by cells of various organs and tissues Trental improves blood microcirculation
Ginipral - a drug to relax the myometrium of muscle tissue and reduce pressure in the uterine cavity
No-Shpa is used to relax the smooth muscles of the uterus

Fetal hypoxia is an intrauterine syndrome characterized by multiple disorders of internal organs and systems caused by oxygen starvation of the fetus. Perinatal hypoxia is one of the most common obstetric pathologies in Russia: up to 10.5% of newborns suffer from certain manifestations of oxygen starvation.

Source: mamitips.com

Causes and risk factors

Fetal hypoxia is a manifestation of various pathological processes in the body of the mother or unborn child. The risk group includes women suffering from anemia and diabetes mellitus, severe forms of preeclampsia, acute and chronic diseases of the respiratory and cardiovascular systems. Contact with toxic substances, living in an ecologically unfavorable area, bad habits of the mother also negatively affect the placental circulation.

On the part of the fetus, the following factors provoking hypoxia are distinguished:

  • malformations and anomalies of development;
  • intrauterine infections (toxoplasmosis, herpes, chlamydia, mycoplasmosis);
  • prolonged squeezing of the head during childbirth;
  • hemolytic disease in Rh-conflict.
Insufficient oxygen supply to the tissues of the fetus triggers a cascade of pathological processes that provoke the appearance of congenital pathologies and the general lag of the child in mental and physical development.

Oxygen starvation of the fetus also occurs with placental blood flow disorders associated with complications of pregnancy and childbirth:

  • fetoplacental insufficiency;
  • anomalies in the structure of the umbilical cord;
  • repeated entanglement of the umbilical cord around the child's neck;
  • overwearing;
  • prolapse or compression of the umbilical cord;
  • prolonged or rapid childbirth;
  • risk of preterm birth.

Source: dobrenok.com

Forms

Depending on the duration of the course, two forms of fetal hypoxia are distinguished - acute and chronic. Acute hypoxic conditions usually develop as a result of pathological childbirth, less often during pregnancy in the case of placental abruption and uterine rupture. The rapidly growing inhibition of the functions of vital organs poses a threat to the life of the child.

Chronic fetal hypoxia during pregnancy develops over time. Insufficient oxygen supply to the tissues of the fetus triggers a cascade of pathological processes that provoke the appearance of congenital pathologies and the general lag of the child in mental and physical development. The first reaction of the body to oxygen deficiency is the centralization and redistribution of blood flow in favor of the brain, which creates the prerequisites for ischemic changes in tissues. The reactive release of vasoactive adrenal hormones in the early stages of hypoxia leads to a gradual depletion of the medulla and cortex and secretory insufficiency, followed by the development of bradycardia and arterial hypotension. Reduced tone of precapillaries and arterioles contributes to the expansion of peripheral vessels and the appearance of capillary circulation disorders, which are expressed in slowing blood flow, increasing blood viscosity and reducing the intensity of gas exchange. Violation of the trophism of the vascular walls increases the permeability of the cell walls, creating conditions for the development of hemoconcentration, hypovolemia, internal hemorrhages and tissue edema. The accumulation of underoxidized metabolic products causes respiratory metabolic acidosis and activates lipid peroxidation, during which toxic free radicals are released.

With the timely passage of planned diagnostic procedures during pregnancy, there is a chance to save the fetus and minimize damage to the health of the child.

The severity of pathological changes in chronic perinatal hypoxia depends on the duration and intensity of oxygen deficiency, as well as on the adaptive capabilities of the body. In obstetric practice, compensated, subcompensated and decompensated hypoxic conditions are distinguished. Compensated fetal hypoxia during pregnancy does not cause serious damage to the health of the child, but the probability of the birth of absolutely healthy children after hypoxia suffered in the prenatal period is estimated at 4%.