What is weak labor in humans? Other diseases from the group Pregnancy, childbirth and the postpartum period. How does pathology manifest itself?

– contractile activity of the uterus is insufficient in strength, duration and frequency, due to its hypotonic dysfunction. Weakness of labor is manifested by rare, short-lived and ineffective contractions, slower dilation of the cervix and the advancement of the fetus. Pathology is diagnosed through observation, cardiotocography, and vaginal examination. In the treatment of weakness of labor, labor stimulation is used; carried out according to indications C-section.

Weakness of labor may be due to the late or young age of the primigravida; gestosis; premature birth or post-term pregnancy; hyperextension of the uterus with multiple pregnancy, large fetus, polyhydramnios; disproportion between the sizes of the fetus and the pelvis of the woman in labor (narrow pelvis); early departure water The development of weakness of labor can be caused by placenta previa, pregnancy occurring in conditions of chronic placental insufficiency, fetal pathology (hypoxia, anencephaly, etc.).

In addition, the weakness of labor can be aggravated by a woman’s asthenia (overwork, excessive mental and physical stress, poor nutrition, insufficient sleep); fear of the mother in labor, an uncomfortable environment, inattentive or rude service. Weakness of labor is often a direct continuation of the pathological preliminary period of labor.

Types of weakness of labor

Based on the time of occurrence, a distinction is made between primary and secondary weakness of labor. Primary weakness is considered to be a situation in which, from the very beginning of labor, insufficiently active (weak in strength, irregular, short-lived) contractions develop. Secondary weakness is spoken of when contractions weaken at the end of the 1st or beginning of the 2nd stage of labor after the initially normal or violent nature of labor.

Types of weakness of labor include segmental and convulsive contractions. Convulsive contractions are characterized by prolonged (more than 2 minutes) contractions of the uterus. During segmental contractions, contraction occurs not of the entire uterus, but of its individual segments. Therefore, despite the continuity of segmental contractions, their effect is extremely small. Definition clinical form weakness of labor allows you to choose differentiated tactics in relation to the treatment of disorders.

Symptoms of weak labor

Clinical manifestations primary weakness labor activity is: decreased excitability and tone of the uterus; frequency of contractions - 1-2 within 10 minutes; the duration of contractions is no more than 15-20 seconds; amplitude (strength) of myometrial contractions - 20-25 mm Hg. Art. The period of uterine contraction is short, the period of relaxation is extended by 1.5-2 times. There is no increase in intensity, amplitude, or frequency of contractions over time.

Contractions with primary weakness of labor can be regular or irregular, painless or slightly painful. The course of structural changes in the cervix (shortening, smoothing and opening of the cervical canal and uterine pharynx) is slowed down. Weakness of contractile activity of the uterus often accompanies the period of expulsion, as well as the afterbirth and early postpartum period, which leads to hypotonic bleeding. Primary weakness of labor leads to prolongation of labor, fatigue of the woman in labor, and untimely effusion amniotic fluid, lengthening the anhydrous interval.

In the case of secondary weakness of labor, initially effective contractions weaken, become shorter and less frequent, until they stop completely. This is accompanied by a decrease in the tone and excitability of the uterus. The opening of the uterine pharynx can reach 5-6 cm without further progression; the progress of the fetus through the birth canal stops. The danger of weak labor activity is an increased risk of ascending infection of the uterus, the development of fetal asphyxia or fetal death. With prolonged standing of the fetal head in birth canal Maternal birth injuries (hematomas, vaginal fistulas) may develop.

Diagnosis of weakness of labor

To determine the nature of labor, a clinical assessment of the effectiveness of contractions, uterine tone, and labor dynamics is carried out. During childbirth, monitoring of uterine contractions is carried out (tocometry, cardiotocography); The frequency, duration, and strength of contractions are analyzed and compared with the norm. Thus, in the active phase of the 1st period, contractions lasting less than 30 seconds are considered weak. and at intervals of more than 5 minutes; for the 2nd period - shorter than 40 seconds.

When labor is weak, the cervix dilates by less than 1 cm per hour. The degree and speed of dilation are assessed during vaginal examination, and also indirectly - by the height of the contraction ring and the advancement of the head. Weakness of labor is indicated if the first stage of labor lasts for more than 12 hours in primiparous women, and more than 10 hours in multiparous women. Weakness ancestral forces should be differentiated from discoordinated labor, since their treatment will be different.

Treatment of weakness of labor

The choice of treatment regimen is based on the causes, the degree of weakness of labor, the period of labor, and an assessment of the condition of the fetus and mother. Sometimes, to stimulate the intensity of contractions, it is enough to catheterize the bladder. If the weakness of labor is caused by In the process of pregnancy management, the obstetrician-gynecologist needs to assess the risk factors for the development of weakness of labor, and if such factors are identified, carry out preventive medication and psychophysical preparation. Weakness of labor almost always leads to a deterioration in the condition of the fetus (hypoxia, acidosis, cerebral edema), therefore, simultaneously with labor stimulation, fetal asphyxia is prevented.

Primary and secondary weakness of labor. Causes, tactics of labor management.

This is the most common type of anomaly of labor forces, mainly occurring in primiparas. It complicates the course of labor in 8-9% of women in labor.

Clinical picture. Weakness of labor is characterized by a duration of labor exceeding 12 hours and even 18 hours (“prolonged labor”), with the average duration of labor in primiparous women being 11-12 hours, in multiparous women - 7-8 hours. A sign of this pathology is the presence of rare, weak, short, unproductive contractions from the very beginning of the first stage of labor. As labor progresses, the strength, duration and frequency of contractions either do not tend to increase, or there is a very slow increase in the intensity of labor. Weak, short, rare contractions lead to slow effacement of the cervix and opening of the uterine pharynx and the absence of forward movement of the presenting part along the birth canal.

After 12 hours of labor, the mother becomes mentally and physically tired; after 16 hours, the energy resources of the mother’s body are exhausted, and the fetus’s tolerance to labor stress decreases.

Primary weakness is often accompanied by premature or early rupture of amniotic fluid, which can contribute to infection of the fetus and birth canal of the woman in labor, fetal hypoxia and even its death.

Primary weakness of labor in the absence of treatment or improper treatment can continue throughout the entire period of dilatation and turn into weakness of pushing. Often, women in labor with primary weakness of labor have a complicated course of the afterbirth and early postpartum periods. Involution of the uterus occurs more slowly in the postpartum period, and endometritis and infectious processes often develop. Unfavorable birth outcomes for the fetus are more common.

Diagnostics. Weakness of labor can be diagnosed after 2-3 hours of observation of the woman in labor. Traditional methods determine the dynamics of the nature of labor and the correspondence of the strength, frequency and duration of contractions to the phase of labor: latent, active (Fig. 70). The opening of the uterine pharynx is monitored using external methods (based on the height of the contraction ring), supported by internal examination data. The use of hysterography facilitates and speeds up diagnosis. When labor is weak, contractions have low intensity and frequency, and a decrease in uterine tone is also observed.

Primary weakness of labor must be distinguished from the pathological preliminary period, since the correction of these conditions is carried out from fundamentally different positions. The irregular nature of contractions and the absence of “structural” changes in the cervix are the main differences between the pathological preliminary period.

Treatment. With primary weakness of labor, treatment should begin as early as possible. To create a favorable background for the action of birth-stimulating drugs, the woman in labor is administered estrogens (estradiol dipropionate, ethinyl estradiol), ascorbic acid, vitamin B^ calcium chloride, riboxin, phospholipids (essential), antispasmodics (for example, a combination of central and peripheral n-cholinolytics - antispasmodic and ganglerone ).

In case of polyhydramnios or oligohydramnios against the background of cervical dilatation of 3-4 cm, the amniotic sac is opened. This manipulation can help enhance labor.

Further therapy is determined by the specific obstetric situation: whether the woman in labor is tired or alert, at what time of day the birth occurs.

If a woman in labor is tired and gives birth at night, she is given short sleep (rest). For this purpose, sodium hydroxybutyrate is used, which is administered intravenously at the rate of 50 mg per 1 kg of body weight of the woman in labor. Sodium hydroxybutyrate has an antihypoxic effect. In case of severe pain, the administration of sodium hydroxybutyrate is preceded by the administration of promedol or pipolfen in medium doses. Usually sleep lasts 2-3 hours. After waking up, there is often a good labor activity is installed spontaneously. If contractions do not intensify on their own, labor stimulation is performed.

If the woman in labor is alert, slept well at night, and birth occurs during the day, then birth-stimulating therapy is prescribed immediately. In modern obstetrics, preference is given to uterine contracting agents administered intravenously. The effect of such drugs occurs quickly, and the strength and frequency of contractions are well programmed. Oxytocin and prostaglandins are most widely used in obstetrics.

Oxytocin is a hormone of the posterior pituitary gland. Its main pharmacological property is the ability to cause strong contractions of the uterine muscles. For intravenous administration, 5 units (1 ml) of oxytocin are diluted in 500 ml of isotonic sodium chloride solution. Start with 6-9 drops/min, then every 10 minutes the number of drops is increased by 5 (but not more than 40 drops/min!). If there is no effect, then the drug infusion should not be continued for more than 2 hours.

To treat primary weakness of labor, you can use the buccal form of oxytocin - desaminooxytocin. Tablets (25 units) are administered per cheek every 30 minutes; if the effect is insufficient, the dose of deaminooxytocin is doubled.

Prostaglandins - biogenic physiologically active substances, which are “local” hormones, actively influence the contractile activity of smooth muscles. Prostaglandins E 2 and P 2a have found use in obstetrics.

Intravenous administration of prostaglandin E 2 (1 mg) and F 2a (5 mg) is carried out by drip, previously diluted in 500 ml of isotonic sodium chloride solution. Begin administration at 6-8 drops/min and increase to 30 drops/min depending on the effect obtained. Prostaglandin E 2 is used in the latent phase, and prostaglandin R. in the active phase of the first stage of labor.

Oxytocin (2.5°IU) can be combine with prostaglandin F 2a (2.5 mg). Then their effect is potentiated, so the dose is reduced by half.

Childbirth is carried out under cardiac monitoring. Every 3-4 hours, fetal hypoxia is prevented, antispasmodics and painkillers (promedol) are prescribed; for a long (more than 12 hours) water-free interval, antibacterial drugs are added.

The use of uterine contracting agents continues throughout labor and ends 30-40 minutes after the birth of the placenta.

Weakness of labor that cannot be corrected is an indication for operative delivery. U For a number of women in labor, cesarean section is performed immediately as soon as the diagnosis of primary weakness of labor is established, without attempts at conservative treatment, which is contraindicated for them. In this

the group includes women with a narrow pelvis, scars on the uterus and cicatricial changes on the cervix, in the presence of a large fetus, with incorrect positions and breech presentation, fetal hypoxia, complicated obstetric history and older age of the first-time mother.

SECONDARY WEAKNESS OF LABOR

This pathology is much less common than the primary one. It complicates 2% of births. With this pathology, a secondary weakening of contractions occurs - usually at the end of the period of opening or during the period of expulsion. Before this anomaly manifests itself, labor progresses at a good or satisfactory pace.

Etiology. The reasons for the development of secondary weakness of labor often have a common nature with the primary one, but the severity of their adverse effects is weaker and the negative impact is felt later. In addition, secondary weakness of contractions may be the result of an obstacle to the advancement of the fetus (discrepancy between the size of the fetus and the mother's small pelvis, incorrect position of the fetus, cicatricial changes in the cervix, tumors in the pelvis). Breech presentation of the fetus, delayed opening amniotic sac, endometritis is often accompanied by secondary weakness.

Secondary weakness of labor may be of iatrogenic origin: indiscriminate prescription of contractile, analgesic and antispasmodic drugs.

Weakness of labor, manifested by unproductive attempts, is identified by some obstetricians as a separate variant of labor. Insufficiency of the anterior muscles abdominal wall in multiparous women, hernias of the white line, umbilical and inguinal hernias, diseases nervous system(poliomyelitis, myasthenia gravis, spinal injuries), obesity - all this can interfere with the development of pushing. Often the weakness of pushing depends on the nature of the presenting part: the pelvic end does not exert proper pressure on nerve endings in the small pelvis. Weakness of pushing can be observed if the woman in labor is tired and the energy capabilities of the uterine muscles are depleted.

Clinical picture. Secondary weakness of labor is manifested by a weakening of the strength of contractions, their slowing down and shortening, and prolongation of the intervals between contractions. The duration of the opening period increases, the advancement of the presenting part slows down or stops. Prolonged standing of the head in one plane of the small pelvis (more than 2 hours) can lead to necrosis of soft tissues with subsequent formation of urinary and fecal fistulas. There is marked fatigue of the woman in labor. Symptoms of associated chorioamnionitis and (or) fetal hypoxia may appear.

Diagnostics. Secondary weakness of labor is diagnosed based on the assessment of contractions, opening of the uterine pharynx and advancement of the presenting part. Dynamic monitoring of these parameters using external and internal obstetric examination makes it possible to make a correct diagnosis in a timely manner. However, hysterography and cardiac monitoring provide more objective information about the nature of contractions and

at the same time they help to detect the slightest signs of fetal distress, which is of great importance for the choice of labor management tactics.

It is very important to make a differential diagnosis between the weakness of labor and the clinical discrepancy between the sizes of the maternal pelvis and the fetal head.

Labor management tactics. Tactics depend on the degree of opening of the uterine pharynx, the position of the head in the pelvis, the condition of the fetus and concomitant obstetric or somatic pathology.

In all situations, treatment of secondary weakness of labor should begin with energy supply to the body and prevention of fetal hypoxia (injections of glucose, vitamins B1B6, C, sigetin, calcium supplements, oxygen inhalation).

If the amniotic sac is intact, then treatment begins with its opening. Perhaps this will lead to increased labor and other interventions will not be required.

When secondary weakness is diagnosed in a tired woman in labor in the first stage of labor with the fetal head pressed or fixed by a small segment at the entrance to the pelvis and the fetus is in good condition, treatment begins with providing a short rest (sleep). After awakening, labor stimulation begins with intravenous administration of uterine contractions.

If secondary weakness occurs when the head is in a wide or narrow part of the pelvic cavity or at the outlet of the small pelvis, birth control therapy is prescribed immediately. The higher the head is, the more active the stimulation should be ( intravenous administration prostaglandin P 2a and oxytocin). If the head is in a narrow part of the pelvic cavity or at the outlet of the small pelvis, you can limit yourself to subcutaneous injections of oxytocin.

The absence or insufficient effect of drug labor-stimulating therapy may force the doctor to change the tactics of labor management to active. Depending on the current obstetric situation perform a cesarean section, apply obstetric forceps or a vacuum extractor, and perform a perineotomy or episiotomy. In the presence of concomitant obstetric and extragenital pathology Caesarean section is carried out immediately after the diagnosis of secondary weakness of labor, without resorting to labor-stimulating therapy

Often the cause of complications during delivery is weak labor activity. As a result of such a violation, Negative consequences can occur both during childbirth and in the postpartum period. Let's take a closer look at this phenomenon, find out what weak labor activity means, highlighting the causes, signs and methods of struggle.

“Weak labor” - what is it?

Before considering pathology, let’s look at the definition and find out: what is weak labor in women and when does it occur. Obstetricians talk about such a disorder when the contractile activity of the uterus does not have the necessary strength to expel the fetus. This is due to changes in the duration and frequency of labor pains. They are rare, short, ineffective. As a result, the process of dilation of the cervix slows down, the speed of fetal advancement decreases, and the development of weak labor is observed.

Weak labor - causes

Due to the fact that the disorder is often provoked simultaneously by several factors, it is problematic to establish the reasons for weak labor in women in a particular case. At the same time, doctors identify several groups of factors that cause disruption of the delivery process. Among them:

1. Obstetric complications:

• early effusion;
• discrepancy between the size of the fetal head and the size of the mother’s pelvis;
• the presence of dystrophic and structural changes in the walls of the uterus (abortion, history of curettage, endometriosis, uterine fibroids);
• rigidity of the muscular layer of the cervix (inextensibility of the organ due to previous operations or diseases);
• abnormal placenta previa;
• gestosis.

2. Pathologies of the reproductive system:

• congenital anomalies of the structure of the uterus (bicornuate, saddle-shaped);
• sexual infantilism (underdevelopment of the reproductive organs);
• chronic inflammatory processes in the uterus;
• violation menstrual cycle;
• diseases endocrine system leading to hormonal imbalance.

3. Extragenital diseases:

• chronic diseases internal organs(pathologies of the liver, kidneys, heart);
• disruption of the endocrine system (obesity, hypothyroidism, diabetes mellitus).

4. Factors due to the baby:

• intrauterine infection;
• intrauterine growth retardation;
• post-term pregnancy;
• premature birth;
• fetal hypoxia;

5. Iatrogenic causes:

• long-term use of birth stimulants;
• neglect of anesthetic measures during childbirth;
• unfounded amniotonia (opening of the amniotic sac by a doctor);
• private vaginal examinations.

Is weak labor inherited?

The belief of some expectant mothers that weak labor is inherited is erroneous. This pathology has no connection with the genetic apparatus, therefore it cannot be inherited from mother by daughter. In most cases, a violation occurs when the delivery process itself is mismanaged and the woman fails to comply with the obstetrician’s requirements. Evidence that the disorder is not related to heredity is the high frequency of its development during childbirth.

Weak labor during the first birth

In order to understand why labor is weak, it is necessary to briefly consider the mechanism of labor itself. So after the dilation of the cervix, the end of the first period, the expulsion phase begins. More often, weakness of labor occurs at the stage of disclosure, a gradual increase in the lumen cervical canal is suspended. As a result, this period of labor is prolonged, the woman in labor loses strength, and becomes very tired. Taking these features into account, among the reasons for weak labor during the first delivery are:

• improper prenatal preparation of a pregnant woman;
• violation of the algorithm for managing the first stage of labor – unnecessary drug stimulation process;
• failure of the mother to comply with the instructions of the obstetricians.

Weak labor during the second birth

Talking about what is associated with weak labor during repeated births, doctors put first priority the violation of the delivery process. A feature of the second and subsequent births is the shortening of the period of opening and expulsion. The contractions increase and become intense over a short period of time. At the same time, there is no competent medical staff nearby who can provide maternity benefit, increases the risk of decreased activity of the uterine structures. The woman in labor loses strength and cannot push productively—secondary weakness.

Weak labor - signs

The diagnosis of “weak labor” is made exclusively by the obstetrician delivering the baby. At the same time, doctors evaluate the nature of contractions and the speed of dilatation of the cervix. The prolongation of the opening period itself is a symptom of the disorder. At the same time, there are signs of weak labor:

• short duration and low intensity of contractions;
• decrease in the speed of fetal advancement along the birth canal;
• increasing intervals between contractions;
• severe fatigue of the woman in labor;
• development of fetal hypoxia.

Weak labor – what to do?

Having experienced this disorder once, women preparing to become mothers for the second time are often interested in the question of how to intensify contractions during weak labor. Initially, everything depends on the mood of the pregnant woman herself, her preparedness for childbirth. Fears, overwork, fear for the unborn baby - have a bad effect on the process of childbirth.

In order to reduce the risk of weak labor, doctors recommend that expectant mothers:

• calm down using non-drug methods(massage, proper breathing);
• during the period of dilation it is necessary to be active - walking, light jumping in place helps the cervix;
• if a woman is forced to accept horizontal position(drip is connected) – you need to lie on the side on which the back of the fetus is located.
• should monitor the condition Bladder– it must be emptied every 2 hours.

Drugs for weak labor

With such a disorder as weak labor, doctors decide how to intensify contractions and stimulate the process based on the degree of pathology and the condition of the woman in labor. The main non-drug method of activating labor is amniotomy - violation of the integrity, opening, of the fetal bladder. The manipulation is performed when the cervix is ​​dilated by 2 cm or more. If there is no effect within 2-3 hours, if weak labor does not disappear, they resort to drug intensification of labor. Among the drugs used:

1. Oxytocin. Administered by drip, intravenously. They begin to use when the cervix is ​​dilated by 5 cm or more and after the opening of the amniotic sac or the release of water.
2. Prostenon. Used in initial stage when the neck does not yet allow 2 fingers through. The drug causes coordinated contractions without disrupting blood circulation in the fetus-placenta system.
3. Enzaprost (Dinoprost). The drug is used during the active dilatation phase, when the lumen of the cervical canal reaches 5 cm or more. The medicine actively stimulates contractions of the uterine myometrium. In this case, there is an increase in blood pressure and blood thickening. This medication is not used in the presence of gestosis or disruption of the blood coagulation system. Administered dropwise, dissolving in physiological solution.

Caesarean section for weak labor

If there is no effect from the drug therapy, deterioration in the condition of the fetus, cesarean section is prescribed for weak labor. Emergency surgical intervention requires highly qualified doctors and the availability of conditions. If weakness occurs during the expulsion period (ineffective pushing and contractions), obstetric forceps are often used. This device helps to extract the fruit out. Timely delivery of childbirth benefits reduces the risk of complications.

Normally, the birth of a child should occur without any complications, both from female body, and from the baby’s side. But in practice, doctors often have to deal with various problems during childbirth, and one of the most common among them is considered to be labor weakness. It is much easier for specialists to correctly resolve problematic situations if the woman in labor herself has accurate information about what weak labor is, knows the causes and symptoms of such a disorder, and roughly understands what to do in such a situation.

Causes

According to obstetricians and gynecologists, there are many factors that can slow down labor. So, such a disorder can develop as a result of neuroendocrine, as well as somatic ailments of the woman in labor. Sometimes it is provoked by overstretching of the uterus, which is often observed with polyhydramnios or multiple pregnancies. In some cases, weak labor is a consequence of complications of pregnancy, pathologies of the myometrium, as well as defects of the fetus itself, for example, disorders of the nervous system, adrenal aplasia, presentation, delayed or accelerated maturation placenta.

Labor may weaken due to too much narrow pelvis mother, the presence of tumors, insufficient elasticity of the uterine cervix.

Sometimes such a violation occurs as a result of the fact that the readiness of a woman and her child for childbirth does not coincide and is not synchronous. In certain cases, weak labor activity is caused by stress, the age of the woman in labor before seventeen or after thirty years, as well as its insufficient physical activity.

Symptoms

Manifestations of weak labor are determined by doctors directly during childbirth. In this case, the woman in labor experiences short contractions of low intensity. The opening of the uterine cervix occurs quite slowly, and the fetus, in turn, moves along the birth canal at a low speed. The intervals between contractions, instead of decreasing, begin to increase, and the rhythm of uterine contractions is also disrupted. Childbirth is particularly long, which causes extreme fatigue for the woman in labor. With weak labor, the fetus experiences a lack of oxygen, which can be monitored using CTG.

If we're talking about about the primary type of labor weakness, contractions are characterized by low severity and insufficient effectiveness from their very appearance. The secondary form of pathology begins to develop after the normal onset of labor.

What to do?

The actions of an obstetrician-gynecologist with the development of labor weakness depend primarily on the causes of such a disorder. Unfortunately, doctors now decide to speed up labor more often than may be necessary. Quite often, the first birth actually takes a very long time, and if the fetus is not threatened by hypoxia, there is simply no point in stimulation. In certain cases, in order for labor to resume, the woman in labor needs to calm down and rest a little.

If labor weakness actually poses a threat to the mother or child, specialists take measures to stimulate it.

Amniotomy, the process of opening the amniotic sac, is considered to be a fairly safe non-drug method for enhancing labor. This procedure can be carried out if the cervix is ​​dilated by two centimeters or more. The rupture of water often leads to intensified contractions, as a result of which the woman in labor can do without medicines.

In some cases, specialists decide to put a woman into medicated sleep for about two hours, which allows her to somewhat restore the strength and resources of her body. To carry out such a manipulation, a consultation with an anesthesiologist and a competent analysis of the child’s condition are required.

To directly accelerate and intensify contractions, ureotonic stimulants can be used. Most often, obstetricians prefer oxytocin and prostaglandins; they are usually administered intravenously using a drip. At this time, the fetal heartbeat is monitored using CTG.

In parallel with stimulant drugs, antispasmodics, analgesics or epidural anesthesia are often used, since a sharp increase in contractions during the administration of drugs is extremely painful. And such a list of drugs can negatively affect the child’s condition; accordingly, they are used only according to indications, if the harm from such a correction is lower than from a protracted labor.

In the event that all the above measures do not give positive result, a decision is made to perform an emergency caesarean section.

What can an expectant mother do?

You need to prepare for childbirth long before the X date. It is advisable to choose a maternity hospital where the woman in labor will feel comfortable, and you also need not to be afraid upcoming birth and get as much information as possible about this process. To prevent labor weakness, it is extremely important to be active after contractions occur - walk, use a fitball, wall bars etc. The right approach to childbirth, confidence in a favorable outcome, support from loved ones and qualified obstetricians help reduce the likelihood of developing labor weakness to a minimum.

Modern obstetrics sets itself the task of making the birth process as safe as possible. One of the problems that leads to complications is the weakness of labor - important reason acute fetal hypoxia. Lack of oxygen can occur with a long period of labor and the use of drugs that stimulate muscle tone uterus.

What is the essence of the problem

Weakness of labor is manifested by insufficient strength and duration of contractions of the muscular layer of the uterus, an increase in the interval between. In connection with this, the smoothing of the cervix and its opening slow down. The fetus also progresses at a slower pace, which can cause injuries and disorders. early adaptation newborns, perinatal lesions.

On the mother's side there is a high probability operative delivery, bleeding, infectious complications in the postpartum period. Reasons for violations contractility uteruses are numerous, they affect all links in the formation of childbirth.

The modern classification of weakness of labor distinguishes primary and secondary forms of pathology. Primary dysfunction occurs from the very beginning of labor and continues until the birth of the fetus. With secondary contractions, contractions weaken after a period of good labor.

Causes of the pathological condition

Weakness of contractions during labor can occur as a result of insufficient quantity and low intensity of impulses that cause and support labor, the inability of the uterus to perceive and adequately respond to them, in the presence of obstacles to childbearing. Emerging causes are usually divided into several groups:

Related to the obstetric situation

Discrepancy between the size of the woman's pelvis and the fetal head, premature passage amniotic fluid, anatomical features reproductive organs, gestosis, multiple pregnancy, large fruit, polyhydramnios, inflexibility and immaturity of the cervix, breech presentation, abnormalities of placenta attachment.

Associated with pathology of the female reproductive system

Neuroendocrine disorders, previous inflammatory diseases of the uterus and appendages, operations on the internal genital organs, abortion, miscarriage, menstrual irregularities, developmental abnormalities, infantilism, infertility, unfavorable outcome of previous births.

From the fetus

Drugs used for weak labor to activate contractions:

• Prostaglandins – Prostenon, Enzaprost, Dinoprost, Prostin, Prostarmon.
• Uterotonics – Oxytocin, Syntocinon, Pitocin.

Exist various schemes using only prostaglandins, uterotonics or a combined administration of these substances. Medicines are administered with strict monitoring of the nature of contractions and fetal heartbeats, using adequate pain relief, following recommendations for the duration, dosage and speed of administration of uterotonics.

During observation, the following is carried out: tocography, cardiac monitoring of fetal cardiac activity, vaginal examinations of the woman in labor, monitoring the timely emptying of the bladder, general condition women measuring arterial pressure, pulse. Contraindications to labor stimulation are:

• previous operations on the uterus;
• discrepancy between the size of the woman’s pelvis and the presenting part;
• incorrect fetal position;
• signs of fetal distress (hypoxia);
• gestosis, hypertension, bronchial asthma– for prostaglandins;
• extension presentation of the head;
• abnormalities of the mother's pelvis (for example), location of the placenta;
• cervical pathology;
• birth barriers;
• lack of monitoring capabilities.

Activation of labor may be complicated by: incoordination of labor, placental abruption, acute hypoxia fetus, excessively violent contractions, birth trauma.

Clinical recommendations for weak labor include the use of an energetic mixture of drugs at the beginning, which increases the effectiveness of treatment for anomalies of labor and labor stimulation. This complex consists of 20 ml of 40% glucose solution, 2 ml of 5% solution ascorbic acid, 10 ml of a 10% solution of calcium chloride administered intravenously and simultaneous intramuscular administration of 10,000 units of folliculin in 1 ml of ether for anesthesia or 0.2 ml of a 2% solution of sinestrol. In parallel with the administration of these drugs, prophylaxis is carried out intrauterine hypoxia fetus and stimulation of labor.

Labor stimulation schemes

To prevent distress, intravenous administration of 2-4 ml of Sigetin solution in 20-40 ml of 40% glucose is used; if necessary, injections are repeated after 30-60 minutes, but no more than 5 times.

If, after three to four hours of administration of prostaglandins, the cervix smoothes and dilates to four centimeters, they proceed to further stimulation with oxytocin. With an adequate dose of oxytocin, labor activity is normalized to 3-5 contractions in 10 minutes, with a contraction duration of 40 seconds, and there is a dynamics of cervical dilatation of 1 cm/hour.

If contractions do not intensify within 2 hours due to the administration of oxytocin, labor stimulation is considered inappropriate. Lack of effect from the first dose is considered an indication for cesarean section. Stimulation is stopped when signs of acute pain appear, which are an indication for surgical delivery.

Secondary weakness of uterine contractility

Weakening of labor forces during the active phase of labor or during initial normal indicators It is commonly called secondary weakness of labor. Dysfunction can develop:

• if there is a discrepancy between the sizes of the fetus and the mother’s pelvis;
• long anhydrous period;
• large fruit;
• polyhydramnios;
• incorrect insertion of the presenting part;
• as a complication of conduction anesthesia.

Pathology is more common in multiparous women. Predisposing factors for the occurrence of dysfunction, as with primary weakness of contractions.

Secondary weakness occurs after the opening of the obstetric pharynx by 6 centimeters; it is characterized by a sharp weakening, slowing down (3 or less in 10 minutes), shortening of contractions, slowing down or stopping the advancement of the presenting part. Diagnosis of the condition is carried out within 2 hours based on observations of the nature of contractions, opening of the uterine pharynx, and advancement of the fetus. If the diagnosis is not made in a timely manner and the woman in labor is not managed adequately, complications may develop.

Management of childbirth

The doctor’s tactics depend on the obstetric situation - the degree of dilatation of the uterine pharynx, the position of the presenting part, and the condition of the fetus. The best way treatment in the first stage of labor is to provide medicinal rest followed by stimulation of contractions.

When the cervix is ​​dilated 5-6 cm, labor stimulation with prostaglandins is recommended; if the technique is ineffective, within 2 hours they switch to combined administration of drugs. Taking into account the duration of labor and possible bad influence for the fetus of oxytocin, it is prescribed when the uterine pharynx is dilated to 7-8 centimeters.

The dosage and rate of administration of substances are described in the table above. If the activation of contractions with oxytocin is ineffective within 1-2 hours, there are no contraindications and the conditions for the operation are available, a caesarean section is performed. Indications for operative delivery are the onset of fetal hypoxia and the inability to complete labor through the natural birth canal.

If secondary weakness of labor occurs while the presenting part is in the pelvic cavity or exiting it, labor stimulation begins immediately. Perineotomy is performed according to indications. If the period of expulsion is prolonged or fetal asphyxia begins, a vacuum extractor or obstetric forceps are applied; breech extract by the pelvic end.

It is important for obstetricians to promptly distinguish secondary uterine dysfunction from a clinical discrepancy between the sizes of the maternal pelvis and the fetal head. If there is an absolute discrepancy, an emergency caesarean section is performed since vaginal delivery is impossible.

Weakness of uterine contractility is one of the causes of postpartum hemorrhage. In order to prevent a serious complication, the administration of uterotonics is continued during and for an hour after its end.

How to prevent

Prevention must begin with puberty. During puberty, a woman's neuroendocrine system is formed. Nutritious food, moderate physical exercise, favorable emotional background have a positive impact.

During reproductive age, it is recommended to plan pregnancy and carry out treatment on time inflammatory diseases female genital organs, menstrual irregularities. During pregnancy, it is necessary to follow the recommendations of obstetricians on nutrition, regimen and hygiene of pregnant women, and attend a school for expectant mothers to prepare for childbirth.

The readiness of the body for the birth of a child, especially the cervix, is of great importance. Laminaria and Dinoprostone are used as means for cervical ripening. In conditions medical institutions carry out training in advance among women who represent a risk group for the development of anomalies of labor. During childbirth, in order to prevent weakness of contractions, the woman in labor needs comfortable conditions, prolonged presence of a partner, vertical position.