Multiple pregnancy

Multiple pregnancy is a pregnancy in which two or more fetuses develop in a woman's body. Genera of two or more fruits are called pluriparous.

[1], [2], [3], [4], [5], [6], [7], [8]

Epidemiology

The frequency of multiple pregnancy in most European countries ranges from 0.7 to 1.5%. The widespread introduction of assisted reproductive technologies led to a change in the ratio of spontaneous and induced multiple pregnancies: 70 and 30% in the 1980s against 50 and 50% at the end of the 1990s, respectively.

The main factors contributing to multiple pregnancy include the age of the mother over 30-35 years old, the hereditary factor (maternal line), high parity, anomalies of the development of the uterus (doubling), the onset of pregnancy immediately after stopping the use of oral contraceptives against the use of funds for stimulation of ovulation , with IVF.

[9], [10], [11], [12], [13], [14], [15], [16]

Causes of the multiple pregnancies

The causes of multiple fertility are diverse and insufficiently studied. Heredity plays a certain role in the propensity to multiple pregnancies. It is most likely that the propensity to develop a multiple pregnancy can be inherited on the maternal line by a recessive type.

In the emergence of multiple pregnancies, an important role is played by the increase in the level of follicle-stimulating hormone (FSH), which contributes to the maturation of several oocytes. It can be hereditarily determined, and also be a consequence of the drug effect (use of ovulation stimulants, estrogen-progestogen withdrawal, in vitro fertilization). An increase in the level of FSH also explains the fact that the frequency of many fetal pregnancies increases with the age of the woman.

Among women with multiple pregnancies, materi- als predominate.

Multiple pregnancy can result from the fertilization of two or more eggs that are ripe at the same time - bivalent (dissimilar) or dizygotic, twins; as well as the development of two or more embryos from a single fertilized egg - single-egg, or monozygotic, twins.

[17], [18], [19], [20], [21], [22], [23], [24]

Symptoms of the multiple pregnancies

The course of multiple pregnancy in comparison with the singleton has a number of unfavorable features. In addition, the course of pregnancy with a monochorionic type is more unfavorable compared with the bichorial type.

The volume of circulating blood with multiple pregnancies rises by 50-60%, while in single-digit pregnancy it increases by 40-50%. This causes an earlier and frequent development of hemodynamic disorders.

The most frequent complications of multiple pregnancy are:

• premature birth (in 25-50% of cases). The average duration of pregnancy for twins is 37 weeks, and for triplets - 35 weeks;
• spontaneous abortion;
• gestosis of pregnant women are much more frequent and more severe than in single pregnancy;
• bleeding during pregnancy;
• anemia of pregnant women;
• polyhydramnios;
• intrauterine growth retardation.

In multiple pregnancies, the developmental fetal malformations are observed 2 times more often than in singleton fetuses, especially with monozygotic twins.

With multiple pregnancies, varicose veins develop more often. The enlarged uterus displaces the diaphragm, which complicates the activity of the heart, resulting in shortness of breath, tachycardia. A compression of the internal organs of an enlarged uterus can be accompanied by a violation of bowel function, heartburn, frequent urination.

Multiple pregnancy - Course and complications

The course of labor during multiple pregnancies

The course of labor with twins is often accompanied by significant complications. Preterm delivery in multiple pregnancies is observed in almost every second woman. In the course of childbirth, there is often an untimely outflow of amniotic fluid (premature or early), with the possible loosing of the umbilical cord loops of the fetus, its small parts.

Due to overstretch of the uterus, labor can be protracted, as the period of cervical dilatation is prolonged due to the weakness of labor activity.

Often, the period of exile is protracted. Sometimes the presenting part of the second fetus tries to get into the pelvis at the same time, and prolonged labor is necessary so that one head is inserted into the basin.

A fairly frequent complication of the period of exile is the belated rupture of the fetal bladder, which also leads to the prolongation of this period of labor.

Untimely discharge of amniotic fluid, prolongation of labor increases the risk of postpartum purulent-septic complications in the mother and fetal distress.

One of the serious complications of the period of exile is premature placental abruption, caused by a rapid decrease in the volume of the uterus and a decrease in intrauterine pressure after the birth of the first fetus.

Very rare, but extremely difficult complication of the period of exile in case of multiple pregnancies is a collision (cohesion) of twins. Different variants of adhesion of fruits are possible. The head of one fetus is more often attached to the head of the other. This occurs when the first twin is born in the pelvic presentation, and the second - in the head one or the first - in the pelvic presentation, and the second - in the transverse position.

After the birth of the first twin, the second can occupy a transverse position even in the case when it was in the longitudinal direction before the onset of labor, which also causes various complications.

In the consecutive and early postpartum periods, hypotonic bleeding often occurs due to uterine overgrowth.

In the postpartum period, the subinvolution of the uterus is also possible.

The management of labor in multiple pregnancies has its own characteristics. The main factors that determine the management of labor during multiple pregnancies are:

• gestational age;
• the state of the fruit;
• the position of the fruit and the presentation;
• nature of labor activity;
• the integrity of the fetal bladder.

According to the indications, they resort to operative delivery: caesarean section, vaginal delivery procedures (vacuum extraction for the fetal head, operation of the obstetrical forceps application). Indications for planned and emergency cesarean section for multidrug In general, the same as in single pregnancy. It should also be known that a multiple pregnancy with pelvic presentation of the first fetus is an indication for a caesarean section.

With the occipital presentation of the first fetus, the whole fetal bladder, the regular labor and the good fetal condition, the genera actively and expectantly under the cardiomonitor control of the fetus state with the help of the nature of the contractile activity of the uterus, the dynamics of the cervix opening, insertion and lowering of the presenting part of the first fetus, . Prevention of weakness of labor activity, hypotonic bleeding is carried out.

After the birth of the first fetus, not only the fetus, but also the mother's end is bandaged. If this is not done, and the twins are odnoyaytsovoy, the second fruit can quickly die from bleeding through the umbilical cord of the first.

The tactics of the doctor after the birth of the first fetus must be active-expectant. After the birth of the first fetus, the fetal heartbeat is controlled, an external obstetric examination is performed to determine the obstetric situation. If after the birth of the first fetus the general condition of the mother is satisfactory, and the fetus is in longitudinal position and without signs of distress, there is no need for an immediate opening of the fetus of the second twin and its extraction. If after the birth of the first fetus the second fetus was not born for 10-1.5 minutes, the fetal bladder of the second fetus is opened, the amniotic fluid is slowly released and, with the longitudinal position, the birth continues to be conservative. With the transverse position of the second fetus under anesthesia, a combined rotation on the stem of the fetus is performed, followed by its extraction. If the fetus is large, is in the pelvic presentation or transverse position, a caesarean section is performed.

It is possible that midwifery operations can be performed to extract the second fetus, if labor is complicated by weakness of labor or fetal distress. In this case, depending on the obstetric situation, a caesarean section is performed, a vacuum extraction of the fetus by the head, or the fetus is removed from the pelvic end.

When pregnancy is three fruits or more, preference is given to delivery by cesarean section. Caesarean section is also carried out in the case of twin fusion.

Particular attention should be paid to the third (successive) period in case of multiple pregnancy due to the high risk of bleeding. It is necessary to carefully monitor the condition of the woman and the amount of blood lost, to prevent bleeding, including uterotonics.

Born the latter carefully examine. At the same time, attention is paid not only to its integrity, but also to the number of shells in the septum between the fetal bladders.

In the postpartum period with multiple pregnancies, postpartum hemorrhage, sub-evolution of the uterus, post-partum purulent-inflammatory diseases occur more often. Therefore, it is necessary to timely prevent these complications, in particular, to monitor the contraction of the uterus after childbirth and, if necessary, to appoint uterotonics.

Forms

Depending on the number of fruits, they speak of double, triple, quadruple, etc.

There are two types of twins: bipartite (dizygotic) and monozygotic (monozygotic). Children born from a double-faced twins are called twins (in foreign literature - "fraternal or not identical"), and children from identical twins are twins (in the foreign literature - "identical"). Twins can be either one or different sexes, whereas twins are just same-sex.

Twins are the result of the fertilization of two eggs, the maturation of which usually occurs during one menstrual cycle in one and in both ovaries. The literature describes cases of so-called "superfetation" (the interval between fertilizations of two eggs is more than one menstrual cycle) and "superfecundation" (the fertilization of eggs occurs during one ovulatory cycle, but as a result of various sexual acts). With dizygotic double, each embryo / fetus has its own placenta, and each of them is surrounded by its own amniotic and chorionic membranes. Thus, the interstitial septum consists of 4 layers. Such an identical twins is called bihorial biamniotic twins. The frequency of double-sided twins (among twins) is 70%.

In single-egg double, one egg is fertilized, with this type of twins the number of placenta formed depends on the time of division of the single fertilized egg. If the division occurs within the first three days after fertilization, then two embryos, two amnions, two chorions / placenta are formed. The interstitial septum, as in the case of a double-sided double, consists of 4 layers. Such an identical twins are also called bihorial biamniotic twins.

When the division of the egg occurs in the interval 3-8 days after fertilization, then two embryos, two amnions, but one chorion / placenta are formed. The interstitial septum consists of two layers of the amnion. This type of monogamous twins is called monochoric bi-amniotic.

When the egg is divided in the interval 8-13 days after fertilization, one chorion and two embryos are formed, surrounded by a single amniotic membrane, i.e. Interfluoric septum absent. Such an identical twins are monochorion monoamniosic.

The result of the division of a fertilized egg into later periods (after the 13th day) is a fused twins.

Thus, the bichorial can be either a two-and twins, while monochorionic is only identical. The study of the placenta / placenta and the fetal membranes after the birth of the child does not always make it possible to accurately establish the zygote. In the presence of four interfruit shells (which is possible in both mono and dysygotic double), only the different sexes of the children clearly indicate dyszigotism. At the same time, the presence of two interfruit shells clearly indicates a monozygotic double.

In same-sex children, zygosity can be established with additional blood tests (including HLA typing) or a study of the skin biopsy of children.

[25], [26], [27], [28], [29], [30], [31]

Diagnostics of the multiple pregnancies

Before the introduction into clinical practice of ultrasound, the diagnosis of multiple pregnancies was not always simple, often the diagnosis was established late in pregnancy and even during childbirth

Currently, the diagnosis of multiple pregnancy is based on the evaluation of the history of the patient, the results of clinical, instrumental and laboratory research methods.

When collecting an anamnesis, it often turns out that a pregnant woman or her husband is one twins twin. Indication of the possibility of developing a multiple pregnancy may be information that the pregnancy occurred after the stimulation of ovulation or the use of methods of assisted reproduction.

In the first trimester, it is necessary to pay attention to the discrepancy between the size of the uterus and the period of pregnancy - the growth of the uterus, as it were, is ahead of the gestation period. Especially rapid growth of the uterus is observed in the second trimester of pregnancy.

In the late stages of pregnancy, the circumference of the abdomen has a definite value for establishing the diagnosis, the height of the standing of the uterus bottom is greater than it should be for a given term of pregnancy. Sometimes it is possible to palpate many small parts of the fetus and two or more large parts (heads and pelvic ends).

Auscultative sign is the detection in different departments of the uterus of foci of clear listening to the heart tones of the fruit. The double frequency is also indicated by the different heart rate.

Certain value in the diagnosis of multiple pregnancies have biochemical tests: the level of chorionic gonadotropin and placental lactogen is higher than in single-pregnancy. Elevated can also be the level of a-fetoprotein.

The most accurate method for diagnosing multiple pregnancies is ultrasound. Ultrasound diagnosis of multiple pregnancy in early terms is based on visualization in the uterus of several fetal eggs, and from the 5th to 6th week of pregnancy - two or more embryos.

In addition to the early detection of many fetal pregnancies, the echography in the II and III trimesters allows to determine the developmental pattern, position, presentation of the fetus, localization, structure, amount of placenta and amniotic cavities, amniotic fluid volume, congenital developmental defects, fetal status, blood circulation (MIC and FPK) with the help of Doppler, the determination of BPP. Difficulties arise in the ultrasound diagnosis of a long-dead fetus from twins ("paper fruit"), as well as in the presence of fused twins.

Diagnosis of the position and presentation of fruits is especially important before delivery for the selection of the optimal method of delivery.

Possible variants of the position and presentation of fruits in the twins:

• both fetuses - in the longitudinal position (most often):
  • both in the head;
  • both in the pelvic;
  • one - in the head, the other - in the pelvic and vice versa;
• both fetuses in transverse position;
• one fruit in the longitudinal, the other in the transverse position.

Conduction of fetometry during ultrasound reveals a delay in the intrauterine development of one or both fetuses. In addition, dopplerography is performed during ultrasound, which makes it possible to detect a violation of the fetoplacental blood circulation, as well as placentometry, in which the placenta is determined and localized, the placenta structure, the presence of a septum between the amniotic cavities. In the absence of visualization of the septum, one should assume a monoamnotic twins, which is characterized by a high risk in childbirth. Ultrasonic fetometry and placentometry allow in the early stages to detect transfusion syndrome of twins.

Cardiomonitoring control with the use of a non-stress test is also of great importance for evaluating the condition of the fetuses.

Multiple pregnancy - Diagnosis

[32], [33], [34], [35], [36], [37]

Treatment of the multiple pregnancies

Early diagnosis of multiple pregnancies allows us to work out the most correct plan for managing pregnancy and timely to prevent possible complications.

Patients with twins require special attention throughout pregnancy. It is very important to pay attention to the function of the cardiovascular system, kidneys, early symptoms of gestosis. When symptoms of gestosis or other complications of pregnancy appear, hospitalization in an obstetric hospital is necessary. In uncomplicated pregnancy, the patient should be referred to the maternity hospital in 2-3 weeks. Before delivery, and in the presence of triplets - for 4 weeks.

Important during pregnancy are monitoring the increase in body weight and timely measures to prevent anemia.

A serious complication of multiple pregnancies is miscarriage. In itself, multiple pregnancy is a risk of miscarriage. It dictates the need to implement preventive measures to prevent this complication of pregnancy.

In connection with a significant overgrowth of the uterus, the lack of a full-fledged contact belt due to the small size of the presenting part of the fetus during multiple pregnancies, there is a risk of premature discharge of amniotic fluid. To prevent this complication, one should recommend a gentle regimen and prescribe tocolytic agents.

Multiple pregnancy - Doing

Prevention

Prevention of multiple fertility is possible only with the use of assisted reproductive technologies (in vitro fertilization) and consists in limiting the number of transferred embryos.

[38], [39], [40], [41]