From what week of pregnancy do babies survive? Premature baby - chances of survival

A child born before 38 weeks of pregnancy is considered premature. Premature birth can be triggered by many social factors, as well as the health status of the expectant mother and her obstetric history. Newborn premature babies, regardless of the degree of underdevelopment, need special care, especially in the first weeks of life.

Who are premature babies?

A baby born between 22 and 37 weeks of pregnancy, weighing from 500 to 2500 grams and body length from 27 to 45 cm is considered premature. Such children differ from full-term newborns in the incompetence and immaturity of almost all systems and organs of the body, as a result of which special care is required for premature infants.

Signs of prematurity

The main clinical external signs of an immature newborn include disproportionate physique, open fontanels (lateral and small) of the skull, undeveloped fatty tissue or its complete absence, hyperemia of the skin, underdevelopment of the external and internal genital organs, physiological reflexes characteristic of full-term peers. In severe cases, apnea, weakness or lack of muscle tone occurs.

Anatomical and physiological characteristics of the child

Depending on the severity, a baby who was born prematurely has the following anatomical and physiological features:

1. The cardiovascular system is characterized by the presence of tachycardia (150-180 beats/min), muffled tones, and functional hypotension of the newborn. In grades three and four, cardiac septal defects (patent foramen ovale) are often present.
2. Respiratory system. Premature infants have narrow upper respiratory tracts and a high diaphragm, which leads to apnea and respiratory failure. Children with the third and fourth degrees of prematurity are on artificial ventilation for a long time, because... organs are not mature and cannot perform their function.
3. Skin and subcutaneous tissue. In newborns born prematurely, subcutaneous fat is almost completely absent, sweat and sebaceous glands do not function, as a result of which the body is not able to independently regulate body temperature.
4. Gastrointestinal tract. In premature infants, there is functional insufficiency of all parts of the gastrointestinal tract, low enzymatic activity of the pancreas and stomach.
5. Excretory system. Immaturity of the urinary system leads to an imbalance in the electrolyte balance in the body, decompensated metabolic acidosis and a tendency to edema and rapid dehydration.

Causes of prematurity

Statistically, there are several groups of risk factors, in the presence of which women have a high risk of giving birth to a baby prematurely:

1. Socio-biological factors. They assume too early or late pregnancy (parents' age is less than 16-18 or more than 40-45 years), the presence of bad habits in the woman, poor living conditions, and the presence of occupational hazards. In addition, the risk of having a premature baby is higher for those girls who are not observed in the antenatal clinic during pregnancy.
2. Unfavorable obstetric and gynecological history and pathological course of the current or past pregnancy. This includes a history of abortions, miscarriages, multiple births, placental abruption, etc. Women who have an interval between births of less than two years may have a high risk of premature birth.
3. Chronic extragenital diseases of the mother: hypertension, endocrine disorders, chronic infections.

Degrees of prematurity

Clinical classification according to the ICD of premature infants according to three criteria (weight, height, gestational age) involves four degrees of severity:

1. The first degree of prematurity is assigned to the baby if delivery occurs at 36-37 weeks of pregnancy; the weight is at least 2000 g, and the body length is from 41 cm. At the same time, independent breathing and the possibility of breastfeeding are observed. However, the baby needs observation by a pediatrician and monitoring of body thermoregulation.
2. The second degree of prematurity is assigned to a baby who was born at a period of 32 to 35 weeks with a weight of 1501 to 2000 g and a height of 36 to 40 cm. As a rule, such babies have a weak sucking reflex, so the baby has to be fed using a tube with special mixtures, there is low muscle tone, immaturity of the respiratory system.
3. The third degree in children born between 28 and 31 weeks of pregnancy, body weight ranges from 1001 to 1500 g, and height from 30 to 35 cm. Such babies are considered very premature and require intensive care under the supervision of doctors. The baby is in a closed incubator; breast milk or formula is fed through a tube due to the complete absence of the sucking reflex.
4. The fourth degree of prematurity is assigned at birth earlier than 28 weeks from the start of pregnancy, body weight is less than 1000 g, body length is less than 30 cm. In relation to such children, neonatology uses the term “newborns with extremely low body weight.”

Weight of a premature baby by month

The body weight of a premature baby increases maximum in the first six months of life (from 500 to 700 grams per month). By the end of the first year, the weight of a healthy newborn should be 9-10 kg. The rate of weight gain depends on the degree of miscarriage, concomitant diseases, congenital pathologies of organs and systems, and, especially, on the type of nutrition of the baby.

Development of premature babies by month

Modern medicine cannot accurately draw the line between the consequences of prematurity and the pathological conditions that arise in a baby born prematurely. The frequency of neurological, mental and physical disorders is due to harmful effects during the internatal period and their negative impact on the immature central nervous system. However, as babies grow and develop, birth defects are corrected. The table shows the development of a premature baby by month up to a year.

Survival rate of premature babies by week

The chances of survival of a baby born prematurely depend directly on how many weeks it has been developing in the womb. According to the World Health Organization, a fetus is considered viable if it is born no earlier than 22-23 weeks and weighs at least 500 grams. The survival rate at this period is only 10-12%. Those born at 25-28 weeks recover in 60-70% of cases; at 29-30 weeks this figure is already 90%. Babies born at 31 weeks or older have a 95% survival rate.

What are the dangers of being born before 37 weeks?

If a baby is born before 37 weeks of gestation, then he has functional immaturity of all organs and systems. Seven-month-old children typically suffer from acute respiratory failure and central nervous system failure. Such children lag behind their peers not only in physical but also mental development. In addition, underdevelopment of the excretory system can lead to the accumulation of toxins in the body and prolonged physiological jaundice.

Future consequences

The immaturity of the organs of children who are born prematurely can negatively affect their health in the future. The most common complications:

• rickets;
• heart failure;
• hydrocephalus of the brain;
• retinopathy of prematurity;
• early anemia;
• severe diseases of internal organs;
• chronic renal failure;
• psychomotor disorders;
• insufficiency of the endocrine glands.

Care of premature newborns

Nursing of children born prematurely in the maternity hospital is carried out regardless of the degree of prematurity and consists of additional heating of the newborn from the moment of birth, rational oxygen therapy, and dosed feeding. In the delivery room, the baby is immediately dried with warm, sterile diapers and immediately placed in an incubator to prevent heat loss. Premature infants weighing less than 1800 g at birth require supplemental heating for several weeks. The temperature in the room should be 24-25°C.

Bathing of children born prematurely begins every other day at two weeks of age. Weighing is carried out daily; height, head and chest circumference are measured at least once a week. Placing a premature baby on his stomach begins as early as possible, which helps increase the concentration of oxygen in the blood and helps reduce regurgitation and normalize muscle tone.

A healthy premature baby, who is able to maintain normal body temperature without additional heating, is constantly gaining weight and reaches 2000 g, can be discharged home if the umbilical wound is well healed, the hemogram and other laboratory tests are normal. As a rule, discharge is made no earlier than 7-9 days after birth.

Incubator

At the initial stage of nursing a premature baby, an incubator or incubator is used to maintain a constant body temperature and optimal feeding using a tube. There are several types of incubators:

1. Resuscitation. Such an incubator, in addition to heating, has a system for regulating the concentration of oxygen in the air, an ECG, an EEG, and a heart rate monitor. Thanks to modern incubators of this type in nursing departments, it is possible to carry out therapy for newborn children even with minimal vital signs at birth.
2. Transport. Necessary for transporting a newborn, incl. and at low temperatures, equipped with heating, supplied with oxygen. This incubator is lightweight due to the absence of a metal frame; the baby is secured with special belts.
3. Open. Used for nursing children of the first degree of prematurity. Helps maintain a constant body temperature for the newborn. In the absence of complications and constant weight gain, the stay in such an incubator is 7-10 days.

Features of feeding

The first feeding depends on the degree of prematurity, birth weight and general health. In the absence of severe pathologies, a premature baby receives nutrition already on the first day of life: in the first degree, feeding begins 2-3 hours after birth, placing them on the mother’s chest. For grades 2-3, feed from a special horn or tube. A premature baby of the fourth degree with low weight is fed first parenterally, then using a tube with a special mixture.

It is optimal to feed milk or colostrum to a woman’s mammary glands, because it is characterized by a high content of essential protein, electrolytes, polyunsaturated fatty acids (linolenic acid promotes high rates of myelination and prostaglandin synthesis), low lactose content, and a huge amount of antibodies and immunoglobulins that protect newborns from infections.

Clinical examination

Premature babies should be especially carefully observed by doctors after discharge from the maternity hospital to reduce the risk of developing severe pathologies in the future, normalize the rate of weight gain in low-birth-weight infants when bottle-fed, and improve physical development indicators. Examination by a pediatrician during the first month of life is carried out 1 time per week, from 2 to 12 - 1 time per month. Consultation with specialized specialists is necessary only in the first month of life, after only 2 months/year. Preventive vaccinations are administered according to an individual plan.

Video

258 days is how long a baby needs to spend inside the mother’s womb to be born full-term. What if he was born earlier? Daria Kinsht, head of the neonatology department, neonatologist, anesthesiologist-resuscitator at the AVICENNA Medical Center of the Mother and Child Group of Companies, spoke about how often premature babies are born, what is the minimum due date and what developmental problems parents of such children may encounter kids.

Criteria for prematurity

More and more children around the world are born prematurely. WHO reports that more than 2.5 million premature babies are born around the world every year. There are many reasons for premature birth: pathological course of pregnancy, , , chronic diseases of the mother, injuries, previous abortions...

” If birth occurs before the full 37 weeks, the newborn is considered premature.

Expert commentary

The only criterion for prematurity is the gestational age (the number of full weeks of pregnancy that elapsed between the first day of the woman's last menstruation and the moment of cutting the umbilical cord - editor's note). That is, a child born before 37 weeks (even 36 weeks and 6 days) is considered premature. The frequency of birth of premature babies varies in regions (depending on the state of the perinatal, mainly obstetric service) and even in individual maternity hospitals in the same city (depending on the specialization and level of care of a particular institution). In the world, the frequency of premature births is 6-12%, but the trend towards an increase in their number over the past 10 years has continued.

Minimum due date and newborn weight

• Since 2012 in Russia, in accordance with WHO standards, babies born no earlier than 22 weeks and weighing at least 500 grams are considered potentially viable.

Before 2012 in our country, birth before the 28th week of a fetus weighing less than 1 kilogram was regarded as a late miscarriage (but if the child was born alive and lived for more than 7 days, he was registered as premature).

Expert commentary

The minimum due date, according to the rules for registering the birth of children, which the Russian Federation switched to in 2012, is from 22 weeks and above; with a newborn weighing 500 grams or more. Unfortunately, this does not mean that all children born with such a body weight and at such a gestational age are viable, even if they are provided with highly specialized care. The likelihood of not only survival, but also full rehabilitation is higher after 26 weeks of gestation.

It is important to know that children with extremely low weight, born at the very minimum gestational age, sometimes not only survive, but also catch up with their peers in development!

Learn more about baby's weight and gestational age

When doctors assess the condition of a premature baby, they do not rely solely on the due date. Several criteria are important:

1. Obstetric gestational age;
2. Newborn weight;
3. Maturity of the newborn.

Previously, in neonatology, the division of prematurity into 4 degrees was accepted, but now it is not used.

Expert commentary

Currently, the division of premature infants by degree has no practical significance and is not used in neonatology. Only the gestational age at birth is indicated. For example: “prematurity 35 weeks.” By weight, premature newborns can be divided as follows:

• Children born weighing less than 1000 g are considered extremely low birth weight;
• From 1000 to 1500 g - with very low body weight;
• From 1500 to 2000 g - with low body weight.

The correspondence of weight to gestational age is of practical importance.

To make it clear what weight corresponds to what period, we provide a table:

Features of the health of premature babies

A premature baby not only weighs less than a full-term baby, they differ in appearance and have fundamentally different needs.

In extremely premature babies (weight less than 1500 g), the subcutaneous fat layer is almost completely absent. Their skin is very thin, dark red in color, and covered with thick down. The size of the head compared to the body is much larger than that of full-term babies. All fontanelles and junctions of the skull bones are open, the ears are underdeveloped and very soft. The nail plates are very short and do not cover the phalanges of the fingers. The navel is not located in the center of the abdomen, but at its very bottom.

” However, prematurity is determined not only by external signs. A much more important indicator is the maturity (that is, readiness to function in the outside world) of vital organs and systems. The viability and tactics of nursing a premature baby depend on the degree of this maturity.

If a child is born much earlier than expected, then he is not yet ready for independent extrauterine life. For example, they cannot breathe on their own, and immediately after birth they are placed in special incubators (equipment designed to create optimal conditions for nursing a premature baby) with artificial lung ventilation devices.

If the child cannot suck and swallow on his own, then at first he is fed expressed breast milk or special formulas through a tube.

For premature babies in the first weeks of life, air temperature is critical; such babies very quickly overheat or become hypothermic. The incubator is maintained at a constant temperature and humidity. In some cases, water mattresses are installed in incubators, which create conditions similar to those in the womb.

If the baby is born prematurely - up to 37 weeks of pregnancy– he is considered premature.

There are several degrees of prematurity in newborns. Mild ones, as a rule, do not pose a danger to the baby’s health; severe ones require serious medical care.

Mild prematurity

If the baby is born between 32 and 36 weeks of pregnancy, modern medical care allows him to avoid health problems.

Breast milk for premature babies

Full breastfeeding is not always available. Thus, premature babies, as a rule, do not have a sucking reflex - they are fed through a tube. Does not necessarily transfer the baby to artificial feeding. Pumping is the way out.

In some cases, children with mild prematurity do not have time to fully mature their lungs. They require additional assistance with breathing: artificial ventilation or supplemental oxygen in the first days of life.

Many mildly preterm babies have feeding problems. Babies born before 34-35 weeks are not able to suck on their own - they have to be fed with a tube.

Therefore, babies born at this time are forced to stay in the children's department of a hospital or maternity hospital for several more weeks until they can begin to feed themselves.

Additionally, all premature babies may have trouble maintaining their body temperature for several weeks. In this case they are left in kuveze– a special box for newborns – to maintain optimal temperature and monitor cardiac activity and respiration.

In the future, after discharge, parents should Monitor your child's body temperature carefully. Premature babies can easily become overheated or catch a cold.

Average degree of prematurity

The child is born at 28-31 weeks of pregnancy. In children born at this time, the lungs are not yet fully mature for breathing. They usually require assistance in the form of mechanical ventilation or a constant flow of oxygen-enriched air to maintain positive airway pressure.

Most babies with moderate prematurity require such care for a fairly short time.

If the child is on artificial ventilation, he is fed through an intravenous catheter. Children who breathe on their own can feed on mother's milk through a tube until they learn to suck on their own.

Severe degree of prematurity

The baby is born before the 28th week of pregnancy. Previously, such children survived extremely rarely, but modern medicine makes it possible to care for such babies.

Almost all children born at this stage have not yet developed lungs - most of them require artificial ventilation or a flow of air enriched with oxygen.

The lungs can support respiratory functions from 22-24 weeks of gestation, but the alveoli, necessary for normal oxygen absorption, develop only at 28-30 weeks of pregnancy.

In addition, severely premature babies cannot feed themselves and maintain their body temperature. Parents of such children need to understand that the child will stay in the children's department for a long time.

What are the dangers for children being born prematurely?

Babies born before the 37th week of pregnancy may experience problems associated not only with the lack of a sucking reflex.

The shorter the period at which a child is born, the higher his risk of developing various diseases characteristic of premature babies.

Undeveloped lungs

Pulmonary disorders pose the greatest danger. For example, newborn shortness of breath syndrome, in which the baby’s immature lungs cannot fully expand. To inhale, the child has to make significant efforts.

Such children require artificial respiration.

Stopping breathing

In premature babies, the respiratory center of the brain is not yet fully formed. If a person does not breathe quickly enough, commands from the brain stem compensate by breathing deeper.

Newborn babies, on the other hand, breathe shallowly and unevenly, and have periods of too slow breathing. If they occur too often, doctors say development of respiratory arrest, or apnea.

A baby with this disorder needs constant monitoring in the first weeks of life. As the child grows, the risk of sleep apnea decreases.

Features of the heart

During intrauterine development, a child's blood practically does not pass through his lungs due to the structural features of the heart. The fetal heart pumps blood from the right ventricle not into the pulmonary artery, but into the aorta through an opening called the ductus arteriosus.

Soon after birth in full-term babies it closes, but in premature babies it may remain open. This leads to increased stress on the lungs and heart. This condition requires medical or even surgical treatment.

Infections, metabolic problems and blindness

Infections affect premature babies more often than babies born at term. One of the reasons for this vulnerability is immaturity of the immune system, in which antibodies in the child’s blood are produced in insufficient quantities.

Also dangerous for premature babies are viral infections, which in other babies cause only mild cold symptoms.

In addition, children born prematurely may have problems with the absorption of nutrients, as well as a lack of hemoglobin associated with the low rate of formation of red blood cells - erythrocytes.

Premature babies may also develop retinal damage - retinopathy of prematurity, without early treatment leading to blindness.

That is why premature babies must remain under the supervision of neonatologists from birth until the moment when their body is ready for independent life.

The most important

A child born even before the 28th week of pregnancy can not only survive, but also over time catch up in development with full-term children.

All premature babies require careful care and medical supervision to avoid diseases caused by the immaturity of their body.

Official documents approved by the Ministry of Health of the Russian Federation on the recommendations of the World Health Organization determine the timing of premature birth, during which it is possible to give birth to a viable child. The criteria regulating the need to provide medical care to a newborn also include the approximate gestational age at which the baby is born.

The birth of a baby is considered optimal at 40 weeks, but only every tenth pregnant woman survives. This is the ideal time to give birth, and in life rarely anything is ideal. At 40 weeks, nature provided the necessary conditions for the birth of a healthy baby, and the birth process passed without complications.

The development of the fetus in the mother's womb must be complete. Clinical studies have shown that small deviations from the pediatric norm do not have a significant effect on the condition of the newborn.

At what age can you give birth to a viable baby? For a long time in modern pediatrics, births between 37 and 42 weeks have been considered full-term. The first obstetric week is counted from the 1st day of the last menstruation and is verified according to ultrasound data in each trimester.

A full-term baby can be delivered from 37 to 40 weeks inclusive. At 36 it is still considered full term, at 41 and 42 – post-term. In the last week, the issue of auxiliary measures to stimulate the labor process or early delivery via cesarean section is decided.

In the WHO recommendations, adopted as a basis in the regulatory documents of the Russian Federation, the main determining criterion for the physiology of the birth of a child at a time determined by nature, and its viability, was the gestational age, and not the weight and height of the newborn, although indicators are also taken into account. A woman gives birth to a full-term baby only at 37, 38, 39 and 40 weeks. From 22 to 36 it is considered premature, at 41 and 42 – post-term.

Degrees of prematurity and indicators

Medical assistance to ensure life support for premature birth is provided from the 22nd week of pregnancy, provided that the baby weighs at least 500 g and its body length is 25 cm or more. The statistics include babies born viable who have reached 1 kg and 35 cm in height from the 28th week. From 22 to 27, medical care is provided and the necessary care measures are taken. If such a child has lived for more than a week, he is registered alive.

The main criteria for recording in the medical history by week of pregnancy:

• 22-27 - 4th degree of prematurity, weight from 0.5 to 0.999 kg;
• 28-31 – 3rd degree of prematurity, - 1 kg–1.5 kg;
• 32-35 - 2nd degree of prematurity, - 1,501 kg–2.0 kg;
• 36 (sometimes 36-37) week - 1 degree of prematurity, - 2.001-2.5 kg;
• 37-40 - considered full-term;
• 41-42 – postponed.

According to WHO recommendations, births occurring between 22 and 37 weeks are considered premature. A baby born at 37 weeks is already considered born at the minimum time for physiological birth; if the baby was born a week earlier, he is still not full-term to the lower limit of normal.

Survival at every stage

4th degree of prematurity is a period when the child is not sufficiently prepared for life outside the mother’s womb. It's not just about low weight, but also about the underdevelopment of vital organs. If the maternity hospital has the necessary equipment and specially trained personnel, there is minimal chance of survival of the newborn. Therefore, registration as alive is carried out only from the 28th week, or 7 days after birth.

Grade 3 has approximately a 50% survival rate, causing high mortality in immature lungs. If they were prepared before birth, the baby survives.

In the 2nd and 1st degrees, in modern conditions, it is possible to save almost all children. Despite the 100% survival rate of infants with 1st and 2nd degree prematurity, doctors try to prolong pregnancy at least to the minimum physiological period. No ultra-modern equipment can replace the mother's womb in terms of supply, comfort and optimal natural conditions.

In the weeks when the baby is still considered premature, processes of transition to the outside world occur. The body undergoes radical changes to ensure adaptation outside the mother, the implementation of independent breathing and nutrition.

In order to prevent premature birth, every woman must follow medical instructions, take maximum care of her own body and the unborn child who is about to be born. The baby's life and health depend on the mother.

The probability of survival of the baby is directly dependent on these two factors:

1. Gestation period.
2. Birth weight.

Gestational age, also called the gestational age of the fetus, is an indicator that indicates the number of completed weeks of a woman’s pregnancy.

Reference! Gestational age is counted from the first day of the last menstrual cycle, for the reason that in most cases a woman cannot name the exact date of conception.

The higher the gestational age of a premature fetus, the greater the chance that the baby will survive. According to statistics, a baby born weighing more than 1.5 kg has a greater chance of survival. Infants weighing up to 1.5 kg make up only 1% of live births.

Degrees of fetal development

A premature baby is born before the 37th week of pregnancy. Such children have smaller weight and size indicators than usual, as well as insufficient development of the body as a whole. There are four degrees of fetal prematurity:

An infant is considered to have a chance of survival if its body weight is more than 500 grams.

Let's look in detail at how long a baby can survive:

Important! The activity of a premature baby directly depends on the number of weeks; the longer the baby is carried, the more active it will be.

There is no clearly defined boundary between the degrees, everything depends on the individual development of the child, so one child may have all the signs of prematurity, while another may not have them at all.

How long can a baby be saved?

Premature baby leaves mother's womb early, so the conditions he finds himself in are unsuitable for him:

1. different temperature;
2. pressure;
3. space;
4. air, etc.

Before answering the question of how many weeks babies survive, you need to know that the longer the gestation period, the better the baby adapts to changes.
Each pregnancy case is unique and there is always hope to save the premature baby.

Statistics on premature births show the following:

What measures to take?

Premature birth can occur for various reasons, many of which cannot be controlled, but there are still several rules for parents who want to take care of the health of their unborn baby.

1. Check with a doctor. Ideally, this should be done before conception, for both women and men. Even if everything seems to be in order, it’s worth being safe. After all, various infections can harm the baby in the womb.
2. In a timely manner register for consultation and talk to your doctor about all your medical conditions.
3. Costs avoid direct contact with sick people during pregnancy, so as not to endanger the fetus.
4. Avoid stressful situations throughout the entire pregnancy. If a woman has a very stressful job, it is worth consulting a doctor about taking sedatives.
5. Avoid strenuous physical activity and under no circumstances lift heavy objects. If a woman wants to keep herself in shape, she should do only those exercises that are recommended for pregnant women, and only under supervision, for example, sign up for a fitness class for expectant mothers. It would be better if the trainer draws up an individual program, taking into account the duration of pregnancy and the doctor’s instructions.
6. Costs the same watch your diet so that the baby receives enough nutrients.

First of all, you need to consult a doctor, because each situation is unique in its own way and requires an individual approach.