Abstract
Objective:
Umbilical cord prolapse is a rare event complicating 0.17%–0.62% of all pregnancies. Funic presentation is a known risk factor for umbilical cord prolapse. Currently, there is no strategy to prevent umbilical cord prolapse in patients with funic presentation. The novel technique used is placement of late cervical cerclage to create a mechanical barrier and prevent an umbilical cord prolapse.
Methods:
Six patients with a sonographically detected funic presentation were included in the study. Funic presentation was defined as the sonographic presence of the umbilical cord below the presenting part using both transabdominal and transvaginal sonography. Cord prolapse was defined as an umbilical cord seen or palpated below the presenting part. Cervical cerclage was placed in patients with persistent funic presentations, which is the detection of the umbilical cord below the presenting part, on two or more sonograms at least a week apart.
Results:
Cervical cerclages were placed in six patients with funic presentation between 28 and 34 weeks of gestation without immediate complications. All patients were delivered by a cesarean section between 35 and 38 weeks of pregnancy. None experienced umbilical cord prolapse. Funic presentation was confirmed at birth in all cases. Apgar scores varied between 7 and 10.
Conclusion:
It appears that cervical cerclage may be an effective measure to prevent umbilical cord prolapse in cases of known persistent funic presentation.
An umbilical cord prolapse occurs when the umbilical cord comes out of the uterus before the fetal presenting part. The concern with an umbilical cord prolapse is that pressure, on the umbilical cord, from the fetus will compromise blood flow and oxygenation. 1 An umbilical cord prolapse is a rare event and can complicate 0.17%–0.62% of all pregnancies. 1 Although infrequent, it has been associated with significant perinatal morbidity and mortality.2,3 A funic presentation is the presence of the umbilical cord at below the presenting part, often noted with both transabdominal and transvaginal sonography. A funic presentation (cord pointing toward the lower uterine segment) is a significant risk factor for umbilical cord prolapse. It has been reported in 18% of women in whom clinical prolapse, of the umbilical cord, was detected later. 2
Current management of funic presentation, in the third trimester of pregnancy, is not well defined. It currently consists of frequent sonographic assessments, nonstress tests, and an early delivery, which aims to detect funic presentation, after the fact.1,3 This study presents a new approach, which is a third trimester cervical cerclage, for the mechanical prevention of umbilical cord prolapse, in women with funic presentation. Cervical cerclage provides a mechanical obstruction of the cervix, which will not permit the presenting umbilical cord to prolapse.
Methods
Patients with a sonogram that detected a funic presentation were included in this study. In this study, cord prolapse was defined as an umbilical cord seen or palpated below the presenting part. These patients were chosen based on the diagnosis of funic presentation that was made during a routine third trimester sonogram. In the research institution, assessment of the umbilical cord (structure, presence of these vessels, origin, and location) was a part of every second and third trimester sonogram. Once a funic presentation was suspected, color Doppler was used to definitively confirm the presence of the umbilical cord, loop or loops, below the presenting fetal part. All patients were recruited between June 2012 and July 2018, from either a private practice in Long Island, New York, or a University Medical Center, in Russia. All third trimester patients, with persistent funic presentation, were counseled about a lack of methods to prevent an umbilical cord prolapse. The patients were informed that persistent funic presentation would put them at high risk for umbilical cord prolapse. Patients were also told that although cervical cerclage has been widely used clinically, it had not been offered to patients with funic presentation and potential umbilical cord prolapse. The risks and benefits of a late cervical cerclage placement were discussed with these patients. After extensive counseling, six patients consented to the procedure. None of these patients had had noteworthy comorbidities or pregnancy complications. All patients signed an informed consent for the placement of cervical cerclage. Figure 1 illustrates how a cervical cerclage was placed in a patient with a persistent funic presentation, and this was due to documenting the umbilical cord below the presenting part, on two or more sonograms at least a week apart.
Cervical cerclage placed due to a persistent funic presentation, due to presence of the umbilical cord below the presenting part and seen on two or more sonograms, at least a week apart.
Results
The main study demographics were that maternal age varied from 19 to 36 years, with a mean age of 26 ± 8.2. In addition, the gestational age at the time of diagnosis of funic presentation was between 28 and 34 weeks of pregnancy, with a mean of 31 ± 3 weeks. The technique of cervical cerclage placement was begun by placing the patients in the lithotomy position. The uterine cervix was grasped at 6 o’clock, with ring forceps and traction applied caudally, to expose a posterior fornix. Then, a purse-string suture was inserted with bites of the needle deep enough to suture it to the cervical stroma. Four to six bites of the needle were required to encircle the cervix, and this depended on its thickness. All patients were seen 1 week after cerclage placement, by ultrasonographers, to assess the integrity of the cerclage and umbilical cord location (see Figure 2). The cerclage placement was evaluated using transvaginal sonography with Voluson 730 Expert (GE Healthcare Inc., Milwaukee, WI, USA). 4 The clinical outcomes of the study patients are presented in Table 1.
Diagram of the use of cervical cerclage for a pregnancy with funic presentation.
Clinical Outcomes of Patients Who Underwent Cervical Cerclage for Funic Presentation.
Abbreviation: PROM, premature rupture of membranes.
A vertex presentation was detected in three patients and a breech presentation in the others. The umbilical cord presentation was confirmed in all six cases at the time of delivery. The cervical cerclage sutures were removed prior to cesarean delivery in all cases, without difficulty or complications. All neonates were delivered in satisfactory condition. Apgar scores varied between 7 and 10.
Discussion
A large population-based study by Behbehani et al 5 looked at maternal risk factors for umbilical cord prolapse, based on a total of 16,126 births. The incidence of an umbilical cord prolapse, in that cohort, remained stable throughout that 3-year period. Their incidence was 16.3, 17.0, and 14.7 per 10,000 births, based on births during 2003, 2004, and 2005, respectively. 5 The patients who presented with umbilical cord prolapse were more likely to be native American Indian or Alaskan, multiparous, breech fetal presentation, a prolonged labor, and a male fetus. 5 In that study, a funic prolapse was associated with an increased incidence of placental abruption, fetal hypoxia and demise, excessive bleeding, and a cesarean section.5,6
Ezra et al 2 studied the incidence of umbilical cord prolapse in cases of funic presentation. They reported a 50 times higher relative risk for prolapse than in those patients without funic presentation. Hasegawa et al 6 reported a 38% incidence of funic presentation preceding umbilical cord prolapse. Optimal clinical management of a funic presentation currently does not exist. Patients are usually informed on the risk of an umbilical cord prolapse, in the case of a funic presentation, and this can cause extreme anxiety. 7 Current recommendations include frequent fetal surveillance and delivery by cesarean section around 37 weeks of pregnancy. 7 However, elective delivery at 37 weeks does not solve the problem since the majority of funic prolapses occur prior to this date.5,6
This clinical management strategy is shared on using a cervical cerclage to reinforce the cervix and create a mechanical barrier, in patients with funic presentation and possible prolapse of the umbilical cord. Originally, cervical cerclage was introduced by McDonald to prevent a second trimester pregnancy loss. 8 He reported an outcome in 70 cases of inevitable miscarriage between 20 and 24 weeks of pregnancy. 8 These cases presented with dilation of the cervix and bulging of fetal membranes during the second trimester and all, with one exception, had one or more previous miscarriages. A purse-string suture was inserted around the exocervix on the level of internal cervical os. McDonald reported prolongation of pregnancy in many cases. 8 Since that first description, cervical cerclage gained popularity and underwent numerous modifications (e.g., transabdominal approach). Lately, Shennan et al 9 reported results comparing transvaginal versus transabdominal techniques of cervical cerclage. Complications were rare in women undergoing vaginal cerclage procedure and were related to cerclage failure, cervical trauma, or premature rupture of fetal membranes. However, as in any operative procedure, the outcome of cervical cerclage depends on the strict adherence to the proper surgical technique, including choosing the appropriate site of suture placement. Placing a cerclage at a distance from the external os, of 18 mm or greater, was associated with a lower incidence of spontaneous preterm birth compared with placing the cerclage closer to the external os. 4 The authors have recently reported on the use of sonography to monitor the placement of cervical cerclage in high-risk second trimester patients. The conclusion was that a cerclage stitch placed close to the internal os was associated with a better outcome. 4
In this patient cohort, cervical cerclage was placed upon detecting funic presentation and was removed when fetal membranes ruptured, or delivery was initiated. None of the study patients experienced complications from cervical cerclage or prolapse of the umbilical cord. Late cervical cerclages have been performed previously and are considered safe for the mother and the fetus.7,10 The primary indication for the late cervical cerclage (28 weeks of pregnancy) is dilation and effacement of uterine cervix in the absence of labor. 11 The main absolute contraindications for the procedure are chorioamnionitis, regular uterine contractions, rupture of fetal membranes, vaginal bleeding, and fetal demise. 11 None of these complications were detected in this cohort of patients. Currently, there is no available strategy to prevent umbilical cord prolapse in cases of funic presentation. Most textbooks address the obstetrical management when the umbilical cord prolapse had already occurred. Diagnosis of cord prolapse is made by visual inspection or by palpation during vaginal examination when the umbilical cord is felt below the presenting part after the rupture of fetal membranes. Umbilical cord prolapse is considered an obstetrical emergency requiring immediate delivery. There are several measures to relieve cord compression which should be carried out in cases of umbilical cord prolapse. These measures include manual elevation of the fetal presenting part, the positioning of the patient in steep Trendelenburg exaggerated Sim’s, or knee-chest position. 11 Care should be exercised not to manipulate the umbilical cord as this can result in vasospasm of the umbilical artery. 11
Ahmed et al 12 recommend filling of the urinary bladder as a mean of relieving umbilical cord compression. This method is especially useful if the umbilical cord is prolapsed in patients who reside in a remote area where imminent delivery is not possible. Filling the urinary bladder with normal saline would relieve umbilical cord compression by elevating the fetal presenting part.
Conclusions
In view of a total lack of preventative measures in cases of persistent funic presentation, late cervical cerclage may be a reasonable strategy. None of the patients in this cohort experienced complications, related to cervical cerclage placements. None of these patients, with persistent funic presentation, developed umbilical cord prolapse, after the cervical cerclage placement. The limitation of this study was a relatively small number of participants. The obvious explanation of this limitation is a rare occurrence of persistent funic presentation. Another potential limitation of the study is the lack of routine fetal sonographic assessments in the third trimester of pregnancy. This may further complicate the rate of detection of funic presentation. The strength of this study is an introduction of a new and useful indication for cervical cerclage, closing the cervix to prevent the umbilical cord from prolapsing. In view of high perinatal morbidity and mortality of umbilical cord prolapse, it is felt that placement of cervical cerclage could be added to obstetrical armamentarium. This procedure could provide high-risk patients, with persistent funic presentation, the ability to prevent an umbilical cord prolapse from occurring. In view of high perinatal mortality of umbilical cord prolapsed and the use of cervical cerclage for patients with a persistent funic presentation, ultrasonographers should document funic presentation as part of their clinical practice. It is important to search for umbilical cord loops below the presenting fetal part, and this should be included into routine third trimester sonography. It is also important to assess the placental insertion site of the umbilical cord, as well as true and false umbilical knots.
Footnotes
Declaration of Conflicting Interests
Funding
ORCID iD
