Caesarean section for the benefit of the fetus

Currently, the role of cesarean section in reducing perinatal morbidity and mortality is being studied in depth. A number of studies have established that with the expansion of indications for this operation, perinatal morbidity and mortality decreases, however, these indicators largely depend on the timeliness of determining the condition of the fetus and the time of the operation. Scientists have made a significant contribution to the development of this problem. As early as 1908, N. N. Fenomenov wrote in his manual "Operative Obstetrics" that in the interests of the fetus, a cesarean section should be performed as early as possible from the onset of labor. Scientists note that the role of cesarean section in reducing perinatal morbidity and mortality can be clarified to a certain extent by studying the course of labor that ended in stillbirth or the birth of children in a state of severe asphyxia. The authors showed that in 85% of observations, these births were accompanied by weakness of labor forces, poorly amenable to drug therapy. Some women in labor simultaneously had a post-term pregnancy or a large fetus. In breech births, the combination of weak labor force and a large fetus is especially unfavorable. In this case, the weakness of labor forces that arose in the first stage of labor is renewed or worsened in the second stage in every second mother, causing a severe condition of the newborn. It is noteworthy that the percentage of older primiparous women whose children were born in a severe condition is insignificant. Consequently, the authors conclude, perinatal morbidity and mortality can be reduced by expanding the indications for cesarean section in women in labor with persistent weakness of labor forces, especially in the presence of a large fetus, breech presentation, and post-term pregnancy. But the outcome of cesarean section for the fetus is largely determined by the timeliness of the operation. Scientists point out that perinatal mortality in the case of cesarean section performed during pregnancy was 3%, and the birth of children in severe asphyxia was detected in 4.3% of newborns. The severity of the children's condition was due to severe forms of late toxicosis, premature placental abruption, and extreme prematurity of the children.

In cesarean sections performed during labor lasting up to 16-17 hours, perinatal mortality is significant, and the birth of children in asphyxia is 7%. The duration of labor preceding the operation, over 17 hours, contributed to an increase in perinatal mortality and the frequency of births of children in a state of severe asphyxia. In cesarean sections performed during labor, the severity of the condition of the newborns was most often due to asphyxia and intracranial trauma.

The condition of the newborn depends on the severity of late toxicosis in the mother, the timeliness and method of delivery. In cesarean section, the condition of the children was better when the operation was performed on a planned basis before the development of severe complications in the mother. Caesarean section, as a method of delivery in patients with combined toxicosis, has no advantages over vaginal delivery. However, in case of severe toxicosis and the absence of an effect from intensive therapy, cesarean section is justified, especially in women with suspected immune deficiency. When discussing the tactics of pregnancy and childbirth management in conditions of intensive therapy for severe forms of late toxicosis, it is believed that abdominal delivery is advisable in pregnant women with the most severe course of toxicosis in the absence of a therapeutic effect and the presence of a viable fetus with an immature cervix, as well as deterioration of the condition of the mother or fetus during spontaneous labor.

It is also necessary to pay attention to another circumstance. Thus, according to research data, over the last decade the level of perinatal mortality in the following types of obstetric pathology has decreased: clinically narrow pelvis, uterine scar, abnormal labor. In these groups of pregnant women, no loss of children was observed. At the same time, the perinatal mortality rates in pregnant women with high-risk factors (age over 35 years in primigravidas, aggravated obstetric history, breech presentation of the fetus, extragenital diseases, late toxicosis, etc.) in pathology of attachment and separation of the placenta have not yet been reduced. It is believed that the use of cesarean section in pathology threatening the life of the fetus and newborn, the organization of a department for nursing premature and injured newborns, as well as the availability of specially trained personnel to carry out resuscitation measures and intensive care contribute to the reduction of perinatal mortality.

It is also important to pay attention to another thing. Some authors believe that expanding the indications for cesarean section in the interests of the fetus does not solve the problem of reducing perinatal mortality. A more realistic factor in this regard should be considered the widespread introduction of early diagnostics of intrauterine suffering and fetal hypoxia and their treatment, which allows reducing the frequency of cesarean sections for fetal indications. In this regard, it is necessary to pay attention to other studies. Thus, scientists have shown that a fairly large group - 36.5% - consisted of women in whom abdominal delivery was performed in the interests of the fetus. A comprehensive examination of the fetus in 26.4% of all cases observed made it possible to promptly raise the issue of delivering women by cesarean section exclusively in the interests of the fetus. It is believed that the expansion of indications for surgery is due to the use of complex measures for early diagnostics of fetal hypoxia and the rejection of operative vaginal deliveries that traumatize the fetus. When analyzing the structure of indications for cesarean section in the interests of the fetus, the authors indicate that over the past three decades, the frequency of the operation has increased from 19.5 to 51.3%, mainly due to early detection of fetal hypoxia, which improves the outcome of labor for the fetus and reduces perinatal mortality. At the same time, perinatal mortality after planned operations is significantly lower than after emergency ones. At the same time, some doctors emphasize that cesarean section before the onset of labor is a risk factor for the newborn. The reason for this is the absence of the factor of labor, which is a necessary physiological measure of influence on the fetus, ensuring the timely launch of compensatory reactions of the fetus and the most optimal provision of its transition to extrauterine existence. They also emphasize that the adaptation of children born by cesarean section in the first days of life is more difficult than in physiological births. Therefore, some doctors suggest introducing prednisolone into the umbilical cord vessels of children born by cesarean section.

According to some doctors, the reserves for reducing perinatal and maternal mortality are not associated with an increase in the frequency of cesarean sections, but are embedded in rational management of pregnancy and childbirth, timely diagnosis and treatment of obstetric and extrgenital pathology in antenatal clinics. Most scientists note that a timely operation helps reduce perinatal mortality. Thus, the current state of the issue of abdominal delivery in the interests of the fetus is insufficiently developed, the most informative indicators for performing the operation at the end of pregnancy, during labor, have not been developed. Therefore, when developing indications and contraindications for cesarean section based on clinical and monitoring observations, two main aspects of this problem should be distinguished:

• identification of the most informative signs of fetal distress using various objective methods;
• a comprehensive approach to eliminating fetal dysfunctions and determining the time for a cesarean section, since a late operation with irreversible changes in the organs and systems of the fetus gives prognostically poor results in both the immediate and long-term.

In foreign literature, significant development has been achieved in works that also discuss modern indications for cesarean section in the interests of the fetus. However, a critical analysis of a number of works does not give grounds to speak of a unity in the development of this issue, even in general terms. It is the diversity of positions and points of view that testifies to the complexity of the problem. Quite a few specific studies have been published on this issue in recent years. Their value is beyond doubt. However, it should be noted that it has not yet been possible to achieve any significant methodological results, especially in the comprehensive assessment of the fetus's condition, accessible to a wide range of practicing doctors, and such results were expected with special hopes. At the same time, the role of fetal monitoring in increasing the frequency of cesarean sections in the United States remains controversial. Thus, according to Mann, Gallant, over the past 4 years, the frequency of cesarean sections in the United States has increased from 6.8 to 17.1%, while due to fetal distress it has increased to 28.2%, and then over the past two years it has decreased to 11.7%. An identical pattern is also noted in the work of Gilstrap, Hauth et al.. A particular increase in the frequency of cesarean sections in the interests of the fetus is noted in hospitals functioning as perinatal centers. Analysis of the development trends of this problem of developing indications for this operation revealed significant changes in the disproportion of the pelvis and head of the fetus, bleeding in the third trimester of pregnancy, and abnormal positions of the fetus. At the same time, it should be said that most US institutions disapprove of vacuum traction and vacuum extraction operations of the fetus, obstetric forceps. At the same time, a comprehensive assessment of fetal suffering during labor using cardiotocography and determining the actual pH from the skin of the fetal head (Zaling's test), the identified correlations between fetal pH with fetal decelerations made it possible to reduce the frequency of the threatened state of the fetus from 24.4 to 11.7%. The reduced perinatal mortality rate was 9.8% per 1000 newborns weighing over 1000 g. A number of authors recommend a wider use of cesarean section in hypertensive conditions during pregnancy, in severe forms of late toxicosis, eclampsia. Some authors consider in detail the issue of prenatal fetal distress in the group of high-risk pregnant women, in particular, in such complications as hypertension, late toxicosis, diabetes mellitus, fetal hypotrophy and fetal growth retardation. The authors recommend in such situations to conduct an oxytocin test and in the case of identified hypoxic decelerations of the deep-H type, since with such reactions even normal labor may pose a danger to the fetus. Such pregnant women, according to the authors, should be delivered by cesarean section. Intranatal fetal distress occurs in complicated labor. In this case, fetal suffering (according to the terminology of foreign authors - fetal distress) is possible during premature birth,placenta previa and placental abruption, use of oxytotic agents. The presence of meconium in the amniotic fluid during labor may be an objective indicator of low fetal pO₂ and, thus, fetal suffering. These complications are an indication for monitoring observation during labor, which makes it possible to timely determine fetal hypoxia, thereby causing an increase in the frequency of cesarean sections with a simultaneous decrease in perinatal mortality. In this case, fetal asphyxia manifests itself in the form of hypoxic decelerations. In addition, these decelerations can be caused by compression of the umbilical cord. In this case, if the pH from the skin of the head is 7.25 or lower, this is an indication for surgical delivery.

It is also important to take into account the gestational age, since a cesarean section performed between the 37th and 38th weeks of pregnancy increases the risk of hyaline membrane development by 10 times. This leads to a significant logical conclusion and recommendation - to determine the lecithin/sphingomyelin ratio by amniocentesis to decide on the time of the operation. Some authors note that the frequency of cesarean sections has increased worldwide, and in most cases this increase in the frequency of the operation is associated with indications from the fetus. According to Manuel, Mohan, Sambavi, cesarean sections in the interests of the fetus were performed in 22.5% of women. Jones, Caire, when analyzing trends in the development of indications for cesarean sections based on their own data and materials from 50 other US institutes, showed that cesarean sections are better for the mother and fetus than heavy obstetric forceps. Elert and others noted that due to fetal hypoxia, caesarean section was performed in 32.1%. Thus, in modern obstetrics, the frequency of caesarean section for fetal indications ranges from 26.1% according to Patek, Larsson, to 61.6% according to Eberhardinger, Hirschfeld, and for maternal indications only 5%, in the remaining women mainly with breech presentation of the fetus.

Another difficulty is that the issue of indications for cesarean section depending on the results of monitoring observation of the fetus's condition during pregnancy and labor is not clear enough. As for special research methods, they are known to have appeared later with the development of clinical perinatology. It is believed that, in principle, indications for cesarean section should be based on the most complete fetal examination possible. The authors emphasize that it is necessary to have a good command of the ability to analyze monitoring observation data, then indications for cesarean section can be identified in the initial stages of fetal suffering. The results of a number of studies show that monitoring observation does not entail an increase in the frequency of cesarean sections, but more accurately assesses the fetus's condition intranatally. Given the complexity of this problem, scientists suggest using ultrasound determination of the biparietal size to determine the time of repeated cesarean section. Thus, if the biparietal size at 38 weeks of pregnancy was 9.3 cm or more, the operation could be performed without additional methods for determining the degree of fetal maturity. In these observations, not a single child had hyaline membranes. In half of the clinical observations, the authors performed amniocentesis to determine the lecithin/sphingomyelin ratio, and all children were healthy.

In a number of works, no less attention is paid to the issues of indications for cesarean section and the risk of respiratory distress syndrome in some complications of pregnancy and childbirth. Thus, Goldberg, Cohen, Friedman believe that the presence of labor before the cesarean section did not reduce the risk of respiratory distress syndrome, and only premature placental abruption increased it. The risk of respiratory distress syndrome in newborns is in strict accordance with the gestational age and is possibly higher in children born by cesarean section than in those delivered vaginally.

Some researchers report an increased risk of respiratory distress syndrome depending on the indications for cesarean section, including antepartum hemorrhage, diabetes mellitus, late toxicosis, and abnormal cardiotocography curves. Fedrick and Butler indicate that there was an increased incidence of respiratory distress syndrome among newborns delivered by elective cesarean section (without labor) compared to children delivered surgically with developed labor. Therefore, some doctors suggest intravenous oxytocin with 3-4 uterine contractions 10 minutes apart for 30-60 minutes before surgery to prevent respiratory distress syndrome and hyaline membranes. Thus, the development of respiratory distress syndrome was prevented in 70 newborns delivered between 34 and 41 weeks of pregnancy, and in 13.3% of the control group.

The issue of an increased frequency of cesarean sections in cases where fetal monitoring was used in both pregnant and parturient women remains unresolved. At the same time, Neutra et al. did not find an increase in the frequency of operations with fetal monitoring. Hollmen noted a 35% decrease in blood flow in the intervillous space during cesarean sections using general anesthesia. Hollmen et al. found severe Sang reflexes in neonates in the first two days of life when using prolonged epidural analgesia.

Thus, an analysis of recent literature data shows that it is impossible to speak either of clearly defined indications for cesarean section in the interests of the fetus, or of completely different points of view on this issue.

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