Oxygen, like water, is an indispensable condition of life. During the period of intrauterine development, it is necessary for the proper maturation of tissues and organs, primarily the brain. For a child, the lack of this gas (in medical language, hypoxia) poses a real threat, up to a delay in growth, partial or complete cessation of breathing in the first seconds after birth and mental retardation.
Oxygen can flow intermittently for quite a long time, although the air supply is sometimes sharply reduced at the time of delivery. Acute hypoxia is considered more dangerous than chronic, but in both scenarios the child can be helped.
Oxygen gets to the child through the umbilical cord along with my mother’s blood. In the umbilical cord blood is pumped through the vessels of the placenta, which it is attached to the uterus.
If the uteroplacental blood flow is impaired, the baby begins to receive insufficient amounts of oxygen. This can happen for various reasons.
The risk group includes women suffering from diseases of the blood, blood vessels, heart, nervous system and kidneys. The habits are also imprinted on the course of pregnancy: tobacco, alcohol and drug addiction, even if they are long gone.
In order for doctors to be able to objectively evaluate all the risks, it is important at the first reception to confess their sins and voice their real experience.
Nevertheless, it is impossible to put a definite forecast on the basis of a medical history alone, therefore obstetrician-gynecologists rely on diagnoses that occur only during pregnancy. The threat of premature labor is an alarming signal: with early contractions of the uterus, the vessels of the placenta contract, which means that the baby receives less oxygen. Hypoxia often develops on the background of preeclampsia, especially in its severe forms.
This complication of pregnancy is accompanied by vasoconstriction and increased blood pressure, so the baby suffers again. Diseases associated with impaired functioning of the placenta or umbilical cord (hypoplasia of the placenta, umbilical cord thrombosis) lead to an identical effect.
There are other “possessing” factors, but these are the most common.
The main signs of a lack of oxygen are discoloration of the amniotic fluid and the baby’s heartbeat. Normal amniotic fluid bright.
Depending on the severity of hypoxia, they become greenish, green or dark brown. These unexpected paints are attached to the baby’s feces, which are released into the fetal bladder when the anal sphincter is relaxed (when the muscles no longer receive oxygen, their work is disturbed). If the amniotic fluid has changed its color or shade during childbirth, doctors will fix acute hypoxia.
If the baby’s condition causes great concern about severe gestosis or the threat of premature birth, it may require puncture of the fetal bladder (amniocentesis) or amnioscopy, a special research method that allows you to look behind the septal membranes during vaginal examination.
Both of these methods allow early assessment of the color of amniotic fluid, but there are contraindications to them. For this reason, cardiotocography (CTG) remains the main method for detecting hypoxia. It allows you to measure the baby’s heartbeat, which normally is 140-160 beats per minute.
Over a period of 30–32 weeks during a routine survey, gross violations can be traced, and after 34 weeks, last doubts can be dispelled.
For the same purpose, monitoring of the baby’s heartbeat with CTG is carried out in all women – once a week after 32 weeks and constantly – during childbirth. If the cardiac monitor shows an increase to 180–200 beats before the first period of labor, this means that the baby’s heart is trying to pump more blood to collect more oxygen.
However, this indicator is only an indirect sign of chronic hypoxia: like any chronic process, it can be sluggish or asymptomatic. The doctors will be able to make an accurate diagnosis only after they estimate the color of the amniotic fluid, which usually pours out during the first stage of labor.
But an acute hypoxia CTG monitor captures immediately by a sharp decrease in heart rate. This is a signal for immediate action, because the heart of the baby is working at full capacity.
The future mother can feel the violation of the uteroplacental blood flow herself: if in the third trimester the baby began to move less, you should immediately inform the doctor about it. Reliable failure can be registered according to the results of planned Doppler, which is done to all pregnant women for a period of 28-30 weeks. This study measures the blood flow velocity in the arteries of the uterus, umbilical cord and brain of a baby.
Such a sign as delayed fetal growth also speaks of chronic hypoxia. This problem can be detected at the same time during ultrasound according to fetometry – a method that allows measuring the baby’s weight: when there is not enough oxygen, growth slows down.
The main method of hypoxia treatment is debugging of the uteroplacental blood flow with the help of drugs that improve the access of oxygen to the baby’s tissues. In 85% of cases, this therapy gives the expected result and avoids complications. If a child experiences hypoxia during childbirth – chronic or, more often, acute, the woman is given a highly concentrated oxygen mixture, which is fed through a special oxygen mustache.
Reception is very effective: the supply of air increases, the heart rhythm is aligned, and the color of the amniotic fluid does not change for the worse.
Doctors choose the method of delivery depending on the CTG data, the color of the amniotic fluid and the state of the future mother. In chronic hypoxia, the baby can be born naturally, with acute caesarean section sometimes required.
Episiotomy (dissection of the perineum) can be done to speed up the process, and in fact, and in another case.
To prevent the development of hypoxia, doctors treat preeclampsia and the threat of premature pregnancy.