Oxygen starvation of the fetus during pregnancy occurs in every tenth case. During pregnancy, the baby is in amniotic fluid ah mother. He cannot breathe on his own, so oxygen is transferred to him through the placenta and umbilical cord. If the child stops receiving enough oxygen, he practically “suffocates.”
Fetal hypoxia during pregnancy is considered a serious pathology and can significantly affect the health of the child and even threaten miscarriage. Against the backdrop of a lack of oxygen, irreversible changes may begin in the fetal body, which will subsequently affect its development.
The mechanism of oxygen exchange between mother and child occurs with the help of the umbilical cord through the blood. All substances and gases that the mother consumes are transferred to the fetus. If a woman does not have enough oxygen, the child will definitely experience oxygen starvation. On early stages During pregnancy, this is fraught with developmental anomalies; in later pregnancy, it can lead to delays in growth and development, difficult childbirth, and the inability of the child to adapt to the outside world after birth.
Causes of oxygen starvation in the fetus
Almost all reasons for the development of fetal hypoxia are primarily related to the characteristics of the mother’s life and her diseases. Also, the cause of a lack of oxygen for the child can be a pathology in the development of the umbilical cord or placenta.
Doctors distinguish two types of hypoxia in the fetus:
- acute - develops quickly, usually during the birth of a child;
- chronic - develops over some time when the child is in the womb.
Reason acute hypoxia Various anomalies occur during childbirth: weak labor, wrapping the child in the umbilical cord, compression of the chest and head of the child during the passage of the birth canal.
Chronic fetal hypoxia has many causes that can develop during different stages fetal development and various maternal ailments.
Fetal hypoxia can develop due to diseases in the mother such as:
- Anemia and vegetative-vascular dystonia. Insufficient hemoglobin and low blood pressure cause a lack of oxygen in the mother's blood. Thus, hypoxia also develops in the child.
- Respiratory diseases. Bronchitis, asthma and other diseases of the lungs and bronchi lead to breathing complications. Difficulty breathing can be caused by allergies (hay fever) and a runny nose.
- Diseases of the kidneys and urinary system.
- Diseases of the heart and cardiovascular system.
- Diseases associated with metabolic disorders ( diabetes).
With abnormal development of the fetus, placenta and umbilical cord, hypoxia often appears when: 
- child development delay;
- high water or, conversely, low water;
- post-term pregnancy;
- multiple pregnancy;
- poor blood exchange between mother and placenta;
- infection of the fetus during its intrauterine development.
Oxygen starvation also develops with the following characteristics of the mother’s life:
- drug use, alcohol use, smoking;
- passive smoking;
- specific and difficult working conditions;
- living in places with poor ecology;
- frequent presence in smoky rooms.
Signs and symptoms of oxygen starvation in the fetus during pregnancy
If pregnancy occurs, it is necessary to register with the antenatal clinic and get tested and visit your doctor regularly. Most diseases, including fetal hypoxia, cannot be noticed by a woman on her own.
Symptoms in the early stages are invisible. Main sign lack of oxygen in a child means lethargy, slowdown in development, and attenuation of cardiac activity. Until 18 weeks, a woman practically does not feel the baby’s movement and cannot determine how mobile the baby is and how well his heart is working.
If the fetus stops moving, the mother does not feel its movement within 24 hours, or the tremors become barely noticeable, the woman should urgently seek help. Any delay can cost the child’s health and even life.
Symptoms of child hypoxia during childbirth:
- lack of screaming and movement;
- bluish skin, low temperature bodies;
- with minor hypoxia, the child simply does not have enough air, which is manifested by lethargy and lack of appetite.
Treatment and diagnosis of fetal oxygen starvation
Fetal hypoxia during pregnancy can be determined using tests and intrauterine examination of the fetus. Women who suffer from anemia and diseases internal organs, automatically fall into the risk group.
Oxygen starvation is most quickly determined by undergoing an ultrasound. Children with hypoxia are usually smaller in height and weight. They move less frequently, more slowly (with severe pathology there may be no movement), the heartbeat is slow.
These symptoms may also be signs of another disease. To exclude them, the pregnant woman is sent for Doppler ultrasound - a special study of the placenta, the results of which may indicate a disturbance in metabolism and gas exchange between mother and child. In later stages, a problem with oxygen metabolism can be determined using CHT - fetal cardiotocography. It is used to determine heart rate. Normal frequency The fetal heart rate is between 110 and 160 beats per minute.
If acute hypoxia occurs during childbirth, urgent resuscitation measures may be applied to the newborn, as well as the administration of insulin, glucose and vasodilators.
If oxygen starvation develops gradually, during gestation, therapeutic measures apply not to the child himself, but to his mother.
First, the doctor determines the cause of the lack of oxygen. In the later stages, if there is a threat of miscarriage, measures can be taken to urgently deliver the mother. The child is then placed in a special box using an oxygen mask until his viability is restored. This helps to avoid acute hypoxia during childbirth and does not disrupt the child’s development process.
When found oxygen starvation In the case of a fetus, a pregnant woman is placed in a hospital under the supervision of specialists. If she has infectious or chronic diseases, they are treated first. To ensure normal oxygen exchange between mother and child, it can be used drug treatment. It is carried out using drugs such as Actovegin, Trental, etc. As additional means The use of oxygen cocktails may be recommended.
In most cases, the expectant mother will help to avoid fetal hypoxia by following the rules of a healthy lifestyle. It is necessary to refuse bad habits, primarily from smoking. A pregnant woman is prohibited from being near smokers or in a smoky room. It is necessary to be in the fresh air more often. Regular walking reduces the risk of hypoxia significantly. Pregnant women who are at risk (anemia, low blood pressure, diseases of internal organs) need to eat well and rest often. Regardless of the stage of pregnancy, a woman should not wear tight clothing, uncomfortable underwear, corsets or belts.
Fetal hypoxia is a dangerous pathological process characterized by reduced oxygen supply to the fetus.
Hypoxia occurs due to atypical processes occurring in female body. The time of formation, course and intensity of symptoms directly affect the development and general health of the child. Treatment of hypoxia must be carried out as early as possible so that the disease does not cause irreparable consequences.
Hypoxia can be diagnosed at any stage of pregnancy. The sooner it occurs intrauterine hypoxia the fetus, the more seriously it will affect the child’s development (both mental and physical). It can also cause damage to the central nervous system, but this is in case of untimely or improper treatment. Medical statistics show that oxygen deficiency occurs in 10-15% of all pregnancies. Treatment in this case is primarily aimed at normalizing blood flow to the uterus and placenta, but in case of acute fetal hypoxia, it is recommended to induce labor artificially, and not to apply any methods of treatment.
Intrauterine fetal hypoxia
Causes of intrauterine fetal hypoxia – various pathologies occurring in the maternal body, as well as unfavorable factors external environment. Hypoxia can occur due to diseases:
- hypertension
- diabetes
- heart disease
- preeclampsia and eclampsia
- chronic bronchitis or bronchial asthma
- various kidney diseases
Intrauterine causes of hypoxia:
- damage to the integrity of the uterus
- prolonged compression of the child’s head and neck during childbirth
- complication of the baby’s passage through the birth canal, most often due to large volumes or incorrect position of the baby
- increase in amniotic fluid volume
- pregnancy with two, three or more fetuses
- intrauterine infection of a child
- obstruction of the birth canal from the uterus by the placenta
- wrapping the umbilical cord around the baby's neck
- disruption of blood flow in the placenta
In addition, significant reasons for intrauterine fetal hypoxia can be external factors:
- poor ecology and high air pollution in the place where the expectant mother lives
- reception large quantity medicines
- chemical poisoning
- abuse of alcohol, nicotine or drugs by a woman during pregnancy
Degrees of fetal hypoxia
By flow rate hypoxia is divided into:
- short-term, i.e. occurs quickly and unexpectedly
- moderate severity – expressed directly during childbirth
- acute – signs of the disease are observed several days before the upcoming birth
- chronic fetal hypoxia - it appears when severe toxicosis, incompatibility of blood groups or Rh factors of mother and child, intrauterine infections of the fetus.
By time of occurrence hypoxia is divided:
- formed in the first months of pregnancy
- in the second half of the allotted time
- during childbirth
- occurs very rarely after childbirth.
Symptoms of fetal hypoxia
Hypoxia is quite difficult to determine, since it can appear suddenly. But it is very important to diagnose hypoxia in the early stages, because this will allow you to quickly begin treatment and avoid consequences.
The main symptom of fetal hypoxia is slow heartbeat, but this cannot be noticed at home. The first sign to consult a doctor is change in the intensity of fetal kicks. Every woman feels movement, but if the child makes itself felt less three times per day, you should immediately contact a specialist, because this indicates chronic intrauterine fetal hypoxia.
The acute form, which occurs suddenly, is characterized by completely opposite signs - the child is too active, pushing hard.
Signs of fetal hypoxia in the first three months of pregnancy are very difficult to determine, so it would be better for the woman and the fetus to be examined by a doctor weekly.
Consequences of fetal hypoxia
If you ignore symptoms or contact a doctor late, hypoxia seriously threatens the health and development of the fetus.
Complications chronic fetal hypoxia can become:
- disorders of the development and formation of internal organs, bones and brain of the fetus
- intracellular edema
- internal hemorrhages
- delayed fetal development
For a newborn baby consequences no less serious:
- changes in the structure and structure of some internal organs; hemorrhages
- inability to independently perform functions characteristic of the first days after birth
- neurological diseases
- mental retardation
- psychical deviations
- Cerebral palsy and autism
Acute and chronic fetal hypoxia can lead to fetal death in the womb or death of the child during the first week of life.
How to determine fetal hypoxia
Determining fetal hypoxia starting from the fifth month of pregnancy is not difficult. It is much more difficult to do this in the first 3 months, but the earlier the diagnosis is made, the higher the likelihood of avoiding the consequences of the disease.
Diagnosis of fetal hypoxia consists of:
- with the help of special gynecological diagnostic techniques the transparency, color and amount of amniotic fluid are assessed
- Doppler ultrasound, which allows you to track the speed of blood flow in the umbilical cord and placenta
- listening to heart rate through a stethoscope
- monitoring the intensity of fetal movements
Treatment of fetal hypoxia
At the first manifestation of symptoms of fetal hypoxia, a pregnant woman is immediately hospitalized. The first thing treatment is aimed at is stabilizing the oxygen supply to the fetus and reducing the tone of the uterus. For this, the patient is prescribed strict bed rest and taking medications that will improve oxygen flow and metabolism. Often also prescribed (), which allows increasing blood oxygenation not only in the mother’s body, but also in the fetus.
When the first improvements in the condition of the fetus are observed, the woman can perform gymnastics, various breathing exercises, attend aqua gymnastics. If no measures to normalize the supply of oxygen to the fetus have given the desired effect or symptoms of fetal hypoxia persist for more than twenty-eight weeks of pregnancy, it is best to immediately C-section. In case of acute hypoxia, a newborn child requires the help of a resuscitator.
Prevention of fetal hypoxia
Prevention of fetal hypoxia should be carried out by a woman who has decided to become a mother, namely:
- choose the right way to give birth to a child. A caesarean section is less likely to cause fetal hypoxia than a natural birth.
- timely treatment of diseases that accompany pregnancy
- Avoid strenuous physical activity only breathing exercises
- get enough rest
- rationalize your diet by consuming plenty of vitamins and calcium
- lead healthy image life, give up alcohol, nicotine and drugs
- be regularly observed at the antenatal clinic
- register with an obstetrician-gynecologist on time
- plan pregnancy and carefully prepare for it, through examination by doctors, treatment of chronic, infectious or gynecological diseases
There are many studies related to the treatment of fetal hypoxia. One of them - .
Fetal hypoxia, what kind of phenomenon this is, is known to many expectant mothers. Oxygen starvation is a diagnosis that “scares” many pregnant women. Moreover, this diagnosis is often made without basis, and useless treatment is prescribed. Let's decide how to determine fetal hypoxia, with the help of what studies and guided by what symptoms.
The expectant mother herself may suspect something is wrong from the second half of pregnancy, when she begins to feel the baby’s movements. You need to monitor the frequency of movements very carefully. There should be at least 10 of them per day, meaning at least 10 episodes. For example, a child moved for a couple of minutes - this is one episode. Then an hour later, a couple more minutes - the second episode, etc. There is an opinion that an increase in movements, as well as the so-called “hiccups” of a child, are symptoms of fetal hypoxia, but doctors say that it is much more indicative, on the contrary, a decrease in the number of movements and in general their absence.
If a pathology is suspected, a woman is recommended to perform a CTG - this is an absolutely painless procedure in which the fetal heartbeat is recorded using a sensor. An experienced specialist who has done the decoding will be able to say exactly how the child feels. CTG is usually done not only during pregnancy and if hypoxia is suspected, but also as a planned procedure during childbirth.
Another way to monitor the work of the heart and, in general, the blood supply in the placenta and umbilical cord is Doppler ultrasound. Performed this procedure on equipment for conventional ultrasound, and lasts approximately the same.
A doctor who listens to it through the abdominal wall using an obstetric stethoscope can also suspect something is wrong based on the heart rate. A muffled heartbeat occurs only if the placenta is located along the anterior wall. By the heartbeat, you can determine in what position the fetus is in the uterus, whether it is alone there (at one time, women were diagnosed with multiple pregnancies in this way). The heartbeat begins to be clearly heard through the abdominal wall from the second half of pregnancy. But even at the end of it, you are unlikely to be able to hear the baby’s heartbeat on your own using a phonendoscope. A sharp decrease in heart rate is also a sign of fetal hypoxia. Fortunately, the doctor listens to the baby’s heart at every woman’s visit, so a chronic process can be suspected at an early stage.
In addition, doctors pay attention to ultrasound findings. Pathologies of the placenta can indirectly speak of hypoxia - its thickness is too large or, on the contrary, too small for the term, as well as its detachment and premature maturation. With such diagnoses, women are often admitted to a hospital for preventive purposes.
Also, fetal hypoxia gives symptoms in the case of maternal preeclampsia, diabetes mellitus, severe cough(especially with whooping cough), bronchial asthma, with long stay in a stuffy room, lying on your back (the vena cava is compressed), etc.
The consequences of fetal hypoxia vary depending on whether the condition is acute or chronic. Let's say, when premature ripening placenta or a woman smoking during pregnancy, the fetus regularly lacks oxygen, but this lack is not so obvious as to cause a fatal blow. Children who suffer from hypoxia in utero for a long time are often born weak, with small height and weight, even if they are born to term. Acute hypoxia is much more severe. For example, with complete premature placental abruption, the fetus can die from lack of oxygen in a few minutes. When placental abruption occurs, the connection between the maternal and children's organisms. In case of acute hypoxia, an urgent cesarean section is necessary. This is the only way to save the child.
And if it is sometimes impossible to prevent acute fetal hypoxia, then chronic fetal hypoxia can be successfully combated. First, you need to get rid of bad habits and spend as much time outdoors as possible. Secondly, visit your doctor regularly and do everything necessary tests and examinations in required deadlines. Thirdly, ensure that your diet contains enough iron-rich foods (to avoid iron deficiency anemia– a common cause of chronic fetal hypoxia). And fourthly, do not forget to tell your doctor about any respiratory diseases you have and other chronic diseases of various body systems, if any.
Fetal hypoxia is a multiorgan syndrome associated with oxygen starvation of the fetus during intrauterine development, characterized by a complex pathological changes from many organs and systems.
Fetal hypoxia is recorded at various stages of intrauterine development and is diagnosed in every tenth pregnancy. The development of the fetus as a whole and the process of formation of individual organs and systems depend on the degree and duration of oxygen deficiency. Severe and prolonged hypoxia can result in intrauterine fetal death or the formation of various severe congenital anomalies. The brain, central nervous system and adaptive abilities of the newborn are primarily affected, but changes can affect any other organs.
Until the moment of birth, the fetus does not have independent breathing; the lungs are filled with fluid until birth. The only source of nutrition and respiration for the fetus is the placenta, into which nutrients and oxygen come from the mother's blood. If oxygen transport is disrupted at any stage, oxygen starvation of the fetus occurs and hypoxia develops.
Fetal hypoxia is a dangerous condition that requires immediate medical intervention and correction of the pregnant woman’s health status in order to prevent the development of complications and preserve the life and health of the fetus.
Causes
The development of hypoxia is provoked by many factors, so it is not always possible to clearly indicate the cause and exclude it in advance. There are factors and risks for the development of hypoxia, relative causes that are identified before the onset of hypoxia. dangerous condition. It is aimed precisely at combating them. preventative work obstetrician-gynecologist and the pregnant woman herself.
Fetal hypoxia develops when a number of factors occur related to the health of the mother, fetus, or damage to the placenta.
The most common causes of hypoxia:
- anemia;
- arterial hypertension;
- heart disease, heart failure and other diseases of the cardiovascular system;
- kidney disease, chronic renal failure;
- respiratory diseases - bronchitis, tuberculosis, emphysema, oncology, etc.;
- bronchial asthma;
- diseases immune system, immunodeficiency;
- diabetes;
- endocrine diseases;
- multiple pregnancy;
- STI;
- toxicosis;
- nutritional dystrophy, exhaustion due to lack of maternal nutrition, etc.
Insufficient oxygen supply to the fetus is provoked by chronic intoxication, including industrial intoxication (therefore, it is extremely undesirable for pregnant women to work in industries with high emissions harmful substances into the atmosphere, in paint and varnish production, in many enterprises where there is contact with large amounts of harmful substances). Other sources of chronic intoxication of the mother’s body and, as a consequence, the fetus are alcohol abuse, nicotine and drug addiction.
In terms of the health of the fetus, the causes of hypoxia can be:
- congenital genetically determined anomalies;
- hemolytic disease;
- intrauterine infection;
- umbilical cord entanglement;
- fetoplacental insufficiency;
- head compression;
- intrauterine injuries.
Rh conflict with different Rh factors in the mother and unborn child usually occurs during the second and subsequent pregnancies, if different Rh factors the mother and first-born already had them. If the Rh factors of the mother and the first child coincide, then the likelihood of an Rh conflict occurring during the second pregnancy is not so high.
After the 6-11th week of pregnancy, hypoxia provokes disturbances in the formation of the brain and central nervous system, disturbances in the structure of blood vessels, and the blood-brain barrier. Problems of maturation and formation can affect the kidneys, skeleton, heart, lungs, intestines and other organs.
Hypoxia does not always lead to serious problems. Short-term and minor oxygen starvation is successfully compensated for in subsequent weeks, but if hypoxia becomes chronic or protracted, then the risk of complications increases many times over.
Classification
Based on the duration of its course and the rate of development, hypoxia is usually divided into acute and chronic.
Acute hypoxia is more often observed during complicated, difficult labor and is associated with prolonged or, conversely, rapid labor, prolapse or compression of the umbilical cord, prolonged fixation and compression of the head. Acute hypoxia develops with placental abruption and uterine rupture.
Chronic hypoxia is associated with long-term disruption of oxygen supply to the fetus. Any of these factors provokes a violation of the blood supply to the fetus through the placenta or depletion of blood in oxygen, a violation of the absorption of oxygen by the fetus. All this leads to the development of chronic hypoxia and its complications.
Apgar score
In 1952, the American doctor Virginia Apgar proposed a scale for assessing the condition of a newborn in the first minutes after birth.
Low Apgar scores are not always due to hypoxia of the fetus or newborn, but very often bad condition the newborn is caused precisely by oxygen starvation.
According to the Apgar scale, five objective criteria are assessed from 1 to 3 points:
- Skin coloring.
- Heart rate.
- Reflex activity.
- Muscle tone.
- Breath.
A score of 8-10 points is considered excellent; this is the norm at which you don’t have to worry about the baby’s health. A score of 4-7 points requires attention from the obstetrician. A reassessment takes place five minutes after birth. Usually it rises to 8-10 points; if not, then a careful examination of the baby by a neonatologist is required and a decision is made about additional measures. This is moderate hypoxia, which requires compensation, but usually does not lead to severe consequences. 0-3 points - asphyxia, severe hypoxia, requiring emergency measures, resuscitation.
Symptoms
In the first weeks, it is very difficult to recognize hypoxia; it practically does not manifest itself at all. The presence of risk factors forces the woman and the obstetrician-gynecologist to closely monitor the health of the expectant mother and make an indirect assessment of the condition of the fetus. It is necessary to compensate for possible anemia, ensure good nutrition, relaxation and being in the fresh air.
After the 20th week, the already ripening fetus begins active life activity, the severity and intensity of which can be used to judge its condition. If the fetus suddenly becomes less active, moves less and “kicks” less, then this may indicate the beginning of the development of oxygen starvation; you must immediately consult a doctor for a full diagnosis.
The initial stages of the development of hypoxia are manifested by tachycardia - increased heart rate. The progression of oxygen starvation is indicated by bradycardia (decreased heart rate) and decreased activity, heart sounds are muffled. Impurities of original feces and meconium may appear in the amniotic fluid. This indicates severe fetal hypoxia and requires emergency measures to be taken to save the life of the unborn child.
Diagnostics
At the first signs of hypoxia, the doctor performs auscultation of heart sounds and fetal heart rate. If symptoms of tachycardia or bradycardia are pronounced, further targeted examination is necessary.
Cardiotocography and phonocardiography make it possible to determine the fetal heart rate and its activity. Using Doppler ultrasound, the utero- placental blood flow it is possible to assess the state of the blood supply to the fetus due to the speed and characteristics of blood flow in the vascular bed of the umbilical cord and placenta. At ultrasound examination delayed development and growth of the fetus, depression motor activity. High or low water levels are indirect evidence and predisposing factors in the development of oxygen starvation.
Thanks to amnioscopy and amniocentesis, it is possible to evaluate amniotic fluid, its color, transparency, presence of impurities, and perform biochemical tests.
Treatment
When diagnosing fetal hypoxia, a woman needs hospitalization. Inpatient treatment is carried out to combat obstetric-gynecological and somatic pathologies of the pregnant woman and correct fetoplacental blood circulation. Complete rest, proper nutrition, and exclusion of any external irritants are required.
To correct uterine hypertonicity, papaverine, aminophylline, drotaverine and other antispasmodic drugs are prescribed. To reduce intravascular coagulation - dipyridamole, pentoxifylline, etc.
Drugs that help normalize intracellular permeability - vitamins E, C, B6, glucose, glutamic acid, antioxidants, neuroprotectors.
As additional method For treatment and prevention purposes, ultraviolet irradiation, breathing exercises, and inductothermy are prescribed.
After birth, all children are subject to constant monitoring by a neurologist, pediatrician, and, if indicated, by an orthopedist, pediatric cardiologist, pediatric gynecologist, speech therapist, or child psychiatrist.
Correct and timely prevention of fetal hypoxia consists of preliminary selection of obstetric care and proper management of labor, constant monitoring of the pregnant woman’s condition and prevention birth injuries And intrauterine infections, but first of all it is necessary to pay due attention to collecting the woman’s history and examining her.
Fetal hypoxia is a pathological condition of the fetus due to oxygen starvation, when the necessary oxygen either reaches the fetus in insufficient volumes or is incorrectly utilized by its tissues. It is classified as acute when it occurs suddenly during childbirth, and as chronic when it accompanies the fetus during development. Fetal hypoxia is not an independent nosology, since it indicates only a single circumstance - a deficiency of oxygen required by the fetus for full development.
Intrauterine fetal hypoxia as one of the symptoms accompanies many pathological conditions during pregnancy and childbirth.
Statistically, fetal hypoxia accounts for about 10% of all pregnancies and, accordingly, childbirth.
Not a single biological tissue, be it “young” developing or “adult” fully functioning, is capable of existing without oxygen. It is necessary for both the embryo and the fetus, and for the newly born child. At different periods of intrauterine life, the fetus receives the oxygen necessary for development from different sources.
In the first two weeks, when intensive division of the fertilized egg occurs, it does not have a circulatory system and the cells of the outer layer of the fertilized egg serve as the source of nutrition for the embryo.
At the end of the 10-day period, located in the endometrium ovum begins to actively implant itself into its thickness. This is helped by specially synthesized enzymes that can dissolve the mucous layer, resulting in the formation of a blood-filled cavity into which the future embryo is immersed.
From the 8th to the 16th week, the cells of the membrane surrounding the fetal egg actively divide, forming peculiar “villi” - outgrowths with cavities inside, the blood vessels surrounding the embryo grow into them - the placenta is formed.
After 4 months, the placental blood circulation begins to function fully and begins to deliver oxygen to the fetus. The placenta saturates the blood entering it with oxygen, then transports it to the umbilical cord vein, and from there to the fetal liver and its heart, which distributes the blood to all tissues and organs of the unborn child through special connections - shunts. The lungs of the fetus in utero do not take part in this process, since they become full only towards the end of pregnancy.
The baby takes his first breath after birth, then his lungs “expand” due to the incoming air. From this moment, the blood begins to be redirected to the children's lungs, becoming saturated with oxygen and nourishing all tissues.
Thus, the placenta plays a dominant role in providing oxygen to the fetal tissues, so intrauterine fetal hypoxia is most often associated with disturbances in its structure or functioning. In turn, placental pathology is almost always caused by problems on the part of the mother’s body. Infections (especially chronic ones), endocrine pathologies, cardiovascular diseases and many other conditions significantly worsen placental blood flow and provoke oxygen deficiency in fetal tissues.
Fetal tissues can compensate for a slight oxygen deficiency, but severe oxygen starvation always leads to negative consequences. Depending on the ability of the fetus to adapt to hypoxia without significant damage, hypoxia is classified into three degrees: compensated (first), partially compensated (second) and the most severe - decompensated, third degree. Precise definition the degree of fetal hypoxia allows us to assess its severity and develop adequate treatment tactics.
How to determine fetal hypoxia? First of all, the pregnant woman herself may suspect problems in the condition of the fetus. In conditions of hypoxia, the fetus is uncomfortable, so it begins to behave restlessly, reflexively trying to find a position in the uterine cavity in which it will feel better, that is, it begins to move intensively. Clinically, a pregnant woman feels this in the form of excessive motor activity (“moving”) of the fetus. However, it should be noted that increased fetal movements during hypoxia are observed only in the initial stage, and with hypoxia of the second and third degrees, the fetus becomes inactive, then subsides altogether. Counting the number of fetal movements according to the method proposed by a specialist helps to suspect hypoxia.
It can be reliably diagnosed by a combination of several methods, namely:
- Listening to the fetal heartbeat. Oxygen deficiency causes the fetal heart to contract more intensely in order to “pump” more blood and, accordingly, extract more of the necessary oxygen from it. After 18-20 weeks of pregnancy, the fetal heart beats at a frequency (heart rate) of 140-160 beats/min.
— Cardiotocography (CTG). Allows you to simultaneously measure the frequency of uterine contractions and fetal heart rate.
- Doppler. Helps study blood flow in the vessels of the uterine wall and fetus.
— Ultrasound scanning. Severe fetal hypoxia may be associated with structural changes in the tissues of the placenta, fetal pathology and changes in normal volume amniotic fluid. These changes are clearly visualized during ultrasound examination.
- Amnioscopy. Visual assessment of amniotic fluid (quantity, color, transparency) without compromising the integrity of the amniotic membrane.
Sometimes the diagnosis of fetal hypoxia requires additional measures, for example, hormonal studies.
Treatment of fetal hypoxia is not carried out in isolation from the cause of its occurrence. The prognosis of the pathology depends both on the degree of hypoxia and on timely diagnosis.
Causes of fetal hypoxia
We can say that every pregnant woman has a potential threat of fetal hypoxia. However, it does not always develop even in those who have high risk her appearance. It is very difficult to predict how a pregnant woman’s body will behave over many months, so a specialist first calculates all the existing risks of complications and tries to prevent them. Conclusions like “threatened by intrauterine fetal hypoxia”, “threat of fetal hypoxia”, which often appear in intermediate diagnoses, should not frighten a pregnant woman, since they only mean that the doctor has identified a provoking factor and will try to compensate for it.
It should be noted that it is impossible to list all possible reasons that provoke fetal hypoxia. This condition not only has many causes, it can also appear against the background of a seemingly successful pregnancy. Conventionally, all factors that provoke hypoxia can be classified into those that the pregnant woman’s body possesses; which are implemented by the fetus-placenta circulatory system, as well as on the pathology of the development of the fetus itself.
Prerequisites for impaired oxygen saturation of fetal tissues are created even by a normal pregnancy:
— Pregnancy involves an increased load on the mother’s cardiovascular system. The volume of circulating blood increases by 30%, since there should be “enough” for the fetus, and in order to “pump” it, the heart increases the number of contractions, that is, it begins to work to the limit.
Overestimate influence stressful situations and a difficult psycho-emotional situation during pregnancy is impossible. Strong emotions provoke the release of the “stress hormone” - cortisol, which spasms the walls of any blood vessels, including placental ones. In addition to hypoxia, stress also provokes abnormal uterine contractions, which is fraught with untimely termination of pregnancy.
Another negative factor affecting the condition of blood vessels in the fetus-mother system is smoking. With the participation of nicotine, microthrombi are formed in the placental vessels, and the blood flow changes parameters to pathological ones.
The most common reason disturbances in blood flow in the placenta – its infection. The origins of infectious inflammation may include viruses, fungi, and coccal flora. Under the influence of infection, edema develops in the tissues of the placenta, the walls of blood vessels are damaged, and the viscosity of the blood changes.
The infection can be localized not only in the placenta area. Sometimes it is able to overcome the protective “barrier” of the placenta and penetrate to the fetus. Infection of a fetus accustomed to a sterile environment provokes serious consequences, including intrauterine death.
Sometimes intrauterine hypoxia is provoked by the abnormal location of the placenta, when it is attached to the uterine wall in an area that has a worse blood supply. More often this happens in the presence of abnormalities in the development of the uterus.
Thus, intrauterine fetal hypoxia can accompany many pathological conditions.
Symptoms and signs of fetal hypoxia
IN different terms gestation hypoxia affects differently developing fetus. If it appears in the early stages, it can slow down the formation of the embryo, and in the last trimester its influence is aimed at nervous system fetus, its development and adaptation mechanisms.
Symptoms of fetal hypoxia depend on the degree of disruption of the blood supply to the placenta and, accordingly, to the fetus. To characterize the degree of fetal hypoxia, two important clinical criteria are used - the intensity of fetal movement and its heart rate.
1st degree of hypoxia is characterized as compensated, that is, eliminated by the efforts of the maternal body, when the movements and heartbeat of the fetus become more frequent only occasionally and do not lead to complications.
Stage 2 already has a subcompensated nature, when the risk of failure of adaptation mechanisms increases.
Intrauterine hypoxia of the 3rd degree is said to be decompensated, which means that the fetus is not able to exist normally under conditions of severe oxygen deficiency.
To determine the extent of the effect of hypoxia on the fetus, blood flow in the placenta is studied and the fetal heart rate is measured.
Sometimes experts classify fetal hypoxia not by the duration of exposure to the pathological factor, but by the severity of clinical manifestations. Then the terms “threatening hypoxia” or “incipient hypoxia” are used.
The threat of hypoxia is indicated if obvious signs There is no oxygen deficiency, but there are prerequisites for its occurrence. This situation is provoked by maternal pathologies or changes in the placenta. Threatening hypoxia can become incipient and even chronic, but often with well-developed adaptation mechanisms it remains only at the stage of probability.
If, against the background of well-being, the fetus begins to register the first signs of oxygen deficiency, hypoxia is considered to have begun.
How to determine fetal hypoxia? Often, pregnant women, concerned about the information they have read and the stories of their friends, ask specialists this question. Sometimes, if the risk of developing pathological hypoxia is low, a pregnant woman is taught how to determine fetal hypoxia by the number of its movements. The technique is no different high accuracy, since it is based on subjective feelings. The pregnant woman is asked to take a comfortable position (preferably on her side) and listen to the baby’s behavior, counting the number of his movements. As a rule, movements are felt at least 10 times per hour, and if there are fewer movements, it is worth undergoing an additional examination.
Acute fetal hypoxia
More often, acute fetal hypoxia is diagnosed during childbirth, less often it is diagnosed during pregnancy. The most unfavorable situation is when both forms of hypoxia, acute and chronic, are combined.
Acute hypoxia appears suddenly, develops rapidly and can kill the fetus very quickly. Similar condition It is more often observed during labor, but can also occur before labor begins.
The causes of acute hypoxia are often the incorrect location of the umbilical cord, when it is tightly wrapped around the child many times. This can happen during childbirth, and when the pregnancy is just gestating. The fetal vessels become pinched and oxygen stops flowing to the fetus. Prolonged oxygen starvation leads to the death of fetal brain cells, so the situation requires an emergency solution.
Also, acute fetal hypoxia is diagnosed in the presence of nodes on the umbilical cord, placental abruption, uterine rupture and other serious pathologies.
Complicated labor can cause acute fetal hypoxia. During childbirth, it is often called asphyxia (suffocation). She appears in the background:
— Umbilical cord prolapse and/or compression, when blood through the umbilical vessels suddenly stops feeding the child.
— Placenta previa, when it is located abnormally low and partially prevents the birth of the fetus.
— Abnormal labor activity, especially when the baby’s head “stands” for a long time in the birth canal due to weak pushing.
Diagnosis of fetal hypoxia in acute form is not difficult.
Clinical signs of acute hypoxia:
- Rapid heartbeat of the child, interspersed with its slowdown until the heart stops completely.
— Abnormal motor activity (movement) of the fetus: at first it begins to move too intensely, then the number of movements becomes minimal.
Chronic fetal hypoxia
The chronic form of hypoxia is, of course, a serious condition, but unlike the acute form, it is the most favorable, since it develops gradually, can be detected in the early stages and can be easily treated with timely and proper treatment. Severe forms of chronic hypoxia are rare.
Manifestations of intrauterine hypoxia largely depend on the processes occurring in the placenta, namely in its bloodstream. If the placental circulation is disrupted due to diseases of the mother or fetus, that is, it is secondary in nature, signs of these diseases will first appear (renal failure, severe anemia, etc.).
If intrauterine hypoxia is provoked by a violation of the placental blood flow of a primary nature, the pregnant woman may long time not feel changes in the condition of the fetus and your own, respectively.
The clinical situation with chronic hypoxia, in contrast to acute oxygen starvation, is characterized by a gradual, long-term increase in signs of oxygen deficiency in the developing fetus.
The first symptoms are changes in the fetus’s usual pattern of motor activity and an increase in the beating of its heart.
As a rule, most pregnant women are sensitive to the first signs of trouble in the behavior of the fetus. First of all, when his motor activity becomes unusual. Women feel fetal movements on their own after the 5th month (for those giving birth again - a little earlier) of pregnancy. The number of fetal movements and their intensity per day are distributed unevenly, so increased motor activity alone is of little significance for diagnosis. What is diagnostically important is not the number of fetal movements felt in one “session”, but the alternation of episodes with determination of the interval between them.
Typically, the fetus moves more intensely in the evening, as well as at night; it continues to move for no longer than two minutes (per episode) at one- or two-hour intervals. Conventionally, one or two movements per hour are accepted as the norm. Self-diagnosis in this case can lead to incorrect conclusions, so it is necessary to obtain recommendations for correct calculation from a specialist.
No less important feature Hypoxia is considered to be the fetal heart rate. It is measured during each routine visit to the pregnant woman.
So, if a pregnant woman notices changes in the usual motor activity of the fetus, and the doctor detects a change in the number of its heartbeats, a more detailed diagnosis of fetal hypoxia is necessary.
Treatment of fetal hypoxia
It is useless to treat fetal hypoxia in isolation from its cause. Therefore, the cause is first established, and then the treatment is determined. Acute hypoxia always implies emergency measures, so treatment is carried out according to the specific situation, when the degree of threat to the child is assessed. Unfortunately, in most cases, an acute lack of oxygen requires urgent termination of pregnancy, that is, emergency delivery (caesarean section).
In the treatment of chronic hypoxia, its degree and duration are taken into account. There is a direct relationship between the duration of hypoxia and the severity of its consequences. The formation of the fetus under conditions of prolonged oxygen deficiency depletes its adaptive reserves and inevitably provokes deviations in normal development. It is also necessary to take into account the presence of maternal pathology.
There is no clear algorithm for the treatment of chronic intrauterine hypoxia, because in each individual case it is unique and has a huge number of causes. General principles therapies are:
- Creation comfortable conditions(nutrition, regime, correct physical activity mothers) gestation;
— control and necessary correction of changes in blood coagulation;
- treatment of chronic diseases of a pregnant woman, including those of infectious origin;
- drug improvement of placental blood flow and metabolic processes in the fetus-mother system.
Unfortunately, there is not a single medicine that cures placental insufficiency, does not exist. If the placenta already has an abnormal blood supply, it can only be maintained at a level acceptable for fetal development.
Unfortunately, pregnant women do not always understand that even with good health and the absence of negative symptoms, the fetus may not be as healthy. The first signs of fetal hypoxia are often detected only by a qualified examination, which means it is necessary to carry out all medical recommendations, including preventive treatment.
Consequences of fetal hypoxia for the child
It should be clarified that a child is referred to as a “fetus” if it is still in the uterine cavity. After birth, the fetus is called a child.
Fetal hypoxia inevitably affects the child after birth. Oxygen deficiency during the period of intensive development intrauterine fetus affects the degree of maturation of organs and tissues, the immune and nervous systems. If hypoxia was diagnosed in a timely manner and the fetus was “helped” with medication in time, its consequences for the child will be minimal, or they will not appear at all.
More often, chronic hypoxia provokes:
— malnutrition, that is, a decrease in height and weight; as a rule, the degree of malnutrition correlates with the degree of intrauterine hypoxia;
— weak immunity and, as a result, increased susceptibility to infectious diseases;
- disturbances in the thermoregulation system, when the child experiences temperature fluctuations;
— varying degrees severity of anemia.
With chronic hypoxia, the fetal brain tissue “suffocates”, so at a later age, when the child begins to socialize, he may experience attention disorders, increased excitability and excess activity.
The consequences of acute hypoxia for a child can be severe. More often diagnosed:
Most often, hypoxia during childbirth is provoked by too intense contraction of the uterine wall, especially with the introduction of stimulants such as oxytocin. If during childbirth the fetus is left for a long time without proper blood supply (especially for brain cells), it may die, therefore, in each specific situation, the decision on the method of labor management is made individually. However, if there is a high threat to the life of the fetus, which is almost always the case with acute hypoxia, it is reasonable not to expose it to further risk and immediately remove it from the womb.
Any acute fetal hypoxia during childbirth “has its roots” in the period of gestation, when its prerequisites first begin to form. Therefore, more often than not, if a pregnant woman treats her condition conscientiously, the occurrence of acute hypoxia during childbirth can be prevented.
Prevention of fetal hypoxia
The course of pregnancy and the risk of its complications are significantly influenced by the health of the mother herself. The ideal situation is when a woman planning to become pregnant turns to a specialist to assess her condition and predict the course of her pregnancy. potential pregnancy. This, unfortunately, rarely happens. And although women go to the doctor for this purpose already when they are pregnant, the specialist has time to study the mother’s body if the appearance is early.
For all pregnant women registered, individual plans are drawn up, which indicate potential risks. It is during this period that a conclusion may appear about the possibility of developing hypoxia.
Treatment of pathologies in a pregnant woman must always be carried out, regardless of the condition of the fetus. Treatment of infectious and inflammatory processes of the genital area and anemia is carried out. In case of extragenital pathology (diabetes mellitus, pathology thyroid gland, cardiovascular diseases and others) related specialists are involved in treatment.
Most effective prevention fetal hypoxia is a regular visit to a specialist and conscientious implementation of the recommendations given by him.
It is worth understanding that hypoxia can be prevented by following simple rules:
— visit a specialist in the early stages (up to 12 weeks) and go through all stages of the examination;
- avoid stress and infections;
— monitor existing chronic ailments together with a therapist.