Umbilical cord prolapse is a complication during childbirth, characterized by its location below the adjacent part of the fetus with a violation of the integrity of the fetal bladder. Pathology is not accompanied by subjective clinical signs and is detected only during vaginal examination. Diagnostic measures include internal obstetric examination, ultrasonography. Most often, in order to preserve the life and health of the newborn, emergency operative delivery is carried out, sometimes conservative methods, manual obstetric aid, obstetric forceps are used to correct the position of the umbilical cord loops.
O69.0 Childbirth complicated by umbilical cord prolapse
Prolapse of the umbilical cord is an obstetric complication, expressed by the displacement of the loops of the umbilical cord (its presence in front of the fetus) during or after the outpouring of amniotic fluid in childbirth. Prolapse is distinguished from the presentation of the umbilical cord, in which the pathological arrangement of the loops is observed even before the rupture of the bladder. The incidence of umbilical cord prolapse is 0.15-0.23%, presentation is about 0.6%. Pathology can develop in women of any age, it is more often registered during childbirth with a male fetus, about 60% of cases are noted with head presentation, 25% – with pelvic, 15% – with a transverse position. The loss of umbilical cord loops significantly increases the risk of perinatal mortality.
On the one hand, the umbilical cord prolapse is associated with its abnormal (over 60 cm) length, on the other – with the absence of a contact belt between the parts of the fetus located below (pelvic end or head) and the mother’s bone pelvis. The combination of these conditions during childbirth significantly increases the likelihood of prolapse of the umbilical cord, and prolapse is most often the next stage of its previous presentation. The main risk factors include:
- Position and presentation. The probability of pathology with pelvic presentation increases twenty-fold compared to the head, against the background of leg presentation, prolapse is more common than the buttock. Umbilical cord prolapse is also facilitated by a transverse position. This is due to the lower severity of the contact belt.
- Repeated childbirth. Prolapse in repeat births is caused by the flabbiness of the peritoneum and the relative uterine atony, as a result of which the fixation of the head occurs later than during the first birth. This entails an increase in fetal mobility and can lead first to presentation, and then to prolapse of the umbilical loop.
- The disproportion of the fetus and pelvis. Creates conditions for an obstacle to the insertion of the head into the entrance of the pelvis, changes the mobility of the child. Size mismatch and, as a consequence, prolapse occurs during childbirth with a large fetus, a narrow or excessively wide pelvis, fetal hypotrophy. At risk are women with premature onset of labor, when the fetus has a reduced weight.
- Amniotomy. The opening of the fetal bladder, especially with the rapid subsequent expansion of the perforation, provokes a rapid outpouring of water, the flow can carry away the umbilical cord loop. Most often, the loss as a result of this manipulation occurs against the background of the existing presentation of the umbilical cord or the presence of other predisposing conditions.
Prolapse is often a consequence of anomalies in the insertion of the head (frontal, facial, anterior and posterior pathological asynclitism), abnormal development and attachment (especially presentation) of the placenta, malformations of the uterus (saddle-shaped, two-horned), fetus (hydrocephalus, anencephaly). The probability of umbilical cord loop prolapse increases with multiple pregnancies (for the second and subsequent fetuses), polyhydramnios, rapid childbirth. The risk group includes women in labor with a low-lying or deforming uterine cavity myomatous node.
A change in the position of the child in the uterus is noted before childbirth. The part located closer to the throat (more often – the head, less often – the buttocks or legs) is lowered, inserted into the plane of the pelvis, fixed by a small segment to its bone structures. Then, already during childbirth, during the opening of the cervix, the lower part of the fetal bladder, forming the corresponding uterine segment, forms a separate chamber filled with “anterior” amniotic fluid. The boundary between the two chambers is the so-called belt of contact in the area of the closure of the head with the bones of the pelvis.
Early fixation of the head and a well-defined contact belt prevent the umbilical cord from falling out. In primiparous women, pressing of the head is observed two weeks before delivery, and the opening of the inner and outer pharynx occurs sequentially, which contributes to the small intrauterine mobility of the child, the formation of dense contact of its underlying part with the pelvis. In subsequent childbirth, fixation is noted immediately before the birth process, the external and internal pharynx open in parallel, which is why the mobility of the head is increased, the contact belt is formed more slowly.
Thus, in repeat births for some time there is a kind of “gap” between the baby’s head and the pelvic bones, into which the umbilical cord can prolapse. With breech and especially leg presentation, the contact of the lower part of the fetus with the walls of the birth canal is weak. In the case of a transverse position, the lower segment of the uterus is almost empty, which provokes the umbilical cord loop to fall out into the birth canal earlier than the expulsion of the fetus begins.
The mechanism of pathology development in childbirth with a mismatch in the size of the pelvis of the mother and the head and other disorders is similar. Active labor activity leads to the advancement of the child after the umbilical cord and compression of its dropped loop. If the fetus moves along the birth canal with the head forward, compression of the vessels of the umbilical cord is more pronounced than when inserting the buttocks into the pelvis, therefore, head presentation is more dangerous in terms of the development of perinatal complications.
The loss does not affect the biomechanism of childbirth and its course in any way, therefore, as a rule, it is asymptomatic, which is the greatest danger during childbirth outside a specialized medical institution (however, even in the case of timely diagnosis in such a situation, there is often no time left to save the newborn). Sometimes there is a feeling of discomfort, a foreign object in the vagina, which can be attributed to normal prenatal and birth changes. Obvious signs are detected by the patient only when the loop is hanging outside the vagina.
The loss of the umbilical cord poses a serious threat to the health and life of the unborn child. Compression of the vessels of the displaced umbilical cord by the head or buttocks moving downwards causes asphyxia, which can result in severe, often irreversible damage to the newborn’s brain, which are the cause of various neurological disorders, or the death of a child from acute hypoxia. Spasm of the vessels of the fallen umbilical cord due to its hypothermia entails similar violations. The mortality rate of children during childbirth due to umbilical cord prolapse reaches 16%.
The diagnosis is made by an obstetrician-gynecologist and, as a rule, does not present any particular difficulties, since the prolapsed umbilical cord is easily detected during palpation. To clarify the diagnosis, early diagnosis of pathology, a non-invasive instrumental study is carried out. In addition, during the examination (internal, external obstetric examination, ultrasonography), a number of parameters are determined (presentation, opening of the uterine pharynx, height of the standing of the adjacent part), on which the tactics of childbirth depends.
- Physical examination. When the umbilical cord is presented, the umbilical cord is determined during internal examination as an elastic, convoluted mobile pulsating cord behind the shell wall. Prolapse is diagnosed in the presence of loops in the vaginal tube or outside the vulvar ring. The absence of pulsation indicates umbilical cord prolapse and acute fetal hypoxia requiring emergency delivery.
- Ultrasound scanning. According to the results of obstetric ultrasound with high accuracy, it is possible to identify the abnormal location of the umbilical cord at the stage of opening before rupture of the fetal membranes, which in some cases makes it possible to eliminate the presentation of the umbilical cord before active labor, to prevent its loss. Ultrasound examination also clarifies the nature of fetal presentation.
For a dynamic assessment of the viability of the child until delivery, monitoring of his heart rate is performed using CTG. Differential diagnosis is carried out with the presentation of the umbilical cord vessels – a variant of the umbilical cord sheath attachment with the localization of umbilical vessels in the lower pole of the fetal bladder, above the internal uterine pharynx.
In childbirth complicated by umbilical cord prolapse, emergency hospitalization with immediate delivery is indicated. Treatment should be carried out on the basis of a hospital with the possibility of surgical operation. The obstetrician chooses the tactics of childbirth, therapeutic measures are carried out with the participation of an anesthesiologist, since there is usually a need for manipulations requiring general anesthesia. A newborn needs mandatory neonatologist consultation.
Conservative methods are used in the case of presentation of the umbilical cord. Management without surgical intervention with a fallen umbilical cord is allowed only in the case of full disclosure of the uterus, good labor and pelvic presentation. The umbilical cord can be drawn into the uterine cavity due to the adoption of certain poses in childbirth, which is used in obstetrics. The patient is placed on the side opposite to the dropped loop, or they offer her to take a knee-elbow position with her head lowered and her pelvis raised. Further, childbirth passes through natural ways.
If the prolapse cannot be eliminated, the patient is prepared for operative delivery. Labor activity is stopped by the introduction of beta-adrenomimetics, bringing the knees to the chest. The midwife carefully supports the head during contractions, preventing compression of the umbilical cord until the brigade is fully ready for surgery. The loop that has fallen out of the genital slit is wrapped with a heated sterile diaper to avoid cooling.
Umbilical cord prolapse with a live fetus is successfully treated with surgical methods, preference is given to surgical intervention. Delivery is carried out urgently, since fatal compression of the umbilical vessels can occur at any time. The absence of pulsation in the umbilical cord does not necessarily indicate death – from the moment the pulsation stops, the child lives for five to seven minutes, a quick extraction can save him.
- Manual manual. If the cervix is sufficiently (8 cm or more) open, there is a transverse position or pelvic presentation, a turn on the leg and extraction by the pelvic end is performed. The manual is shown if an emergency delivery is necessary (when the child’s life is counted for minutes), if it is impossible to perform a surgical operation.
- Obstetric forceps. The extraction of the child with the help of obstetric forceps is performed with the full opening of the pharynx and a tightly inserted head or after a successful attempt at conservative reduction of the umbilical cord. In modern obstetrics, forceps are rarely used in complicated childbirth. The indications are similar to those for providing manual assistance.
- Surgical intervention. Cesarean section surgery allows to reduce the perinatal mortality rate from asphyxia caused by a dropped umbilical cord by 6%, reduce the risk of neurological disorders in surviving newborns. Operative delivery is the method of choice for the treatment of this severe obstetric complication with incomplete opening of the uterine pharynx, any presentation and position.
Such obstetric manipulations as colpeyriz, metreiriz, previously widely used during childbirth to stop the outpouring of fetal waters and correct prolapse, have almost lost their relevance today due to low efficiency, high risk of ascending infection, perinatal complications. In case of diagnosed fetal death, they resort to wait-and-see tactics (if labor activity is preserved) or to fruit-destroying surgery.
Prognosis and prevention
The perinatal outcome depends on a combination of many factors – the variant of fetal presentation, the rate of opening of the uterine pharynx, the strength of labor, but mainly on the timeliness of diagnosis and adequate treatment of pathology. Women in labor who are at risk are subject to early prenatal hospitalization with strict bed rest from the moment of the beginning of labor until the head is pressed. Women who have ruptured the fetal bladder outside the hospital also need immediate hospitalization.
Other preventive measures primarily concern the specifics of performing an amniotomy (when indicated for it). The presentation of the umbilical cord is a limitation to the operation. The fetal bladder is opened carefully when the mother is in a position with an elevated pelvis (in this state it should be until the head is fixed). The expansion of the perforation hole is carried out after pouring out a sufficient amount of water. Of no small importance is the treatment at the stage of pre-gravidar preparation of fibroids, as well as diseases that increase the risk of premature birth, fetal development delay.