Absence of Wharton’s jelly

Abstract

Wharton’s jelly is a specialised tissue which surrounds the vasculature within the fetal umbilical cord. We present the case of a 42-year-old woman who gave birth to a female infant via emergency caesarean section. At the time of delivery, absence of Wharton’s jelly was noted. This finding was confirmed by histological examination. Emergency caesarean section was necessitated due to a fetal bradycardia, and of note, the patient had presented twice prior to this with reduced fetal movements.

Background

Wharton’s jelly is a specialised, gelatinous tissue which surrounds the umbilical vessels, namely, two umbilical arteries and one umbilical vein.¹ It acts to support and protect these vessels. Absence of Wharton’s jelly is a rare event, with only a handful of case reports reported in the literature.^2–5 Of the case reports available, each case was associated with either fetal mortality or morbidity.

Case presentation

A 42-year-old primigravida, conceived by in vitro fertilisation with donor egg, presented to the emergency department at 40+2 weeks’ gestation with abdominal pain. This was her third presentation to the emergency department, as she had presented twice previously with reduced fetal movements. On this admission, a cardiotocograph (CTG) was performed. This CTG started with a baseline of 140, reduced variability and no accelerations. Notably, her previous CTG—performed 2 weeks prior—had been reactive. Within 5 min, her admission CTG progressed to a fetal bradycardia of 80 beats per minute, which failed to recover, a category 1 caesarean section was performed for suspected fetal distress. A live female infant was delivered in good condition with of 8 at both 1 and 5 min of life. The infant weighed 3680 g at delivery, greater than the 50th centile for her gestation. Cord gases were taken at birth and showed an arterial pH 7.28 with base excess −3.2 and venous pH of 7.35 with base excess −3.5. Thick, grade 3 meconium and an abnormal umbilical cord was found at delivery. Subsequent pathological examination of the umbilical cord found it to be 410 mm long and free of Wharton’s jelly for 60 mm nearest to the disc. There was meconium staining of all three umbilical vessels, with hypo-coiling. The placenta had a trimmed weight of 736 g and showed evidence of meconium staining (figures 1–3).

Figure 1.

Image of the umbilical cord.

Figure 2.

Umbilical cord with absence of Wharton’s jelly.

Figure 3.

Umbilical vessels visible outside the umbilical cord.

After delivery, the infant was admitted to the neonatal intensive care unit (NICU) post delivery, due to intermittent tachypnoea, secondary to meconium aspiration syndrome. She remained in the NICU until day 14 of life. She was also re-admitted to hospital at day 21 of life with bronchiolitis. No congenital anomalies associated with the umbilical cord abnormality were diagnosed in this case, unlike other published cases. Given the significance of the cord abnormality, this infant was followed up by our neonatology team for 6 months post delivery. No other major abnormalities were diagnosed, and she was found to be developmentally appropriate for her age.

Investigations

Postnatally the umbilical cord and placenta were sent for histopathological examination. This confirmed the absence of Wharton’s jelly around all three umbilical vessels.

The patient’s baby had a full work-up—performed by the paediatric team—and was found to have no evidence of associated anomalies.

Treatment

The patient was well postnatally and did not require any follow-up treatment.

The patient’s infant required respiratory support, via continuous positive airway pressures and inpatient admission until day 14 of life. She also required re-admission to hospital on day 21 of life for a confirmed respiratory syncytial virus infection and bronchiolitis.

Outcome and follow-up

Our patient was due to be reviewed in our postnatal debriefing clinic at 6 weeks postnatal; however, due to the COVID-19 pandemic, this was done virtually via phone call rather than in person. This phone call was used as an opportunity to re-discuss and re-visit the events which led to delivery and also the unusual umbilical cord finding. Unfortunately, due to the paucity of information surrounding absence of Wharton’s jelly in the literature, we were unable to advise our patient on the recurrence rate or the aetiology of the finding. Aside from this, our patient had recovered well postnatally and had no further questions surrounding the delivery.

Discussion

Following this case, we carried out a review of the literature and previously recorded case reports. From this we identified only nine cases with this cord abnormality. Seven of these cases were associated with perinatal death. The other two cases were associated with neonatal morbidity; one with a patent vitello-intestinal duct¹ and the other with profound, psychomotor delay.⁵

Fortunately, our case was not associated with a perinatal death, but the infant did suffer from meconium aspiration syndrome. We also note that this infant had a bradycardic episode in-utero and that our patient presented twice with perceived reduced fetal movements. These events may have been as a result of transient vessel compression in utero. We also note that meconium-stained liquor was a common finding across the documented cases and was present in all but one.

Wharton’s jelly is a specialised connective tissue, thought to provide support and protection to the three umbilical vessels.⁶ These umbilical vessels are paramount to fetal well-being and allow for gasesous exchange to occur between fetus and mother via the placenta. While our case is unique, cord abnormalities as a whole are well documented in the literature and are a known cause of perinatal mortality and morbidity, including intrauterine death and fetal growth restriction.^{7 8}

Without the protection of Wharton’s jelly, the umbilical vessels are vulnerable and at risk of damage and compression. This in turn disrupts fetal blood flow either temporarily or for a prolonged period, resulting in fetal hypoxia and, in some cases, fetal death.

At present, we do not fully understand the pathophysiology behind this abnormality; however, two mechanisms have been suggested. One hypothesis is that the jelly degenerates in-utero with the second suggestion that the abnormality exists secondary to incomplete fusion between the amniotic and mesenchymal tissue.² While the exact mechanism is yet to be understood, we do know that Wharton’s jelly is necessary for cord protection and thus protection of fetal blood supply.

Patient’s perspective.

From the time the baby went into distress, both the midwives and the doctors were so efficient. I was obviously very frightened but they explained what was happening and what would happen next at all points, which helped to keep me calm. When they performed the surgery and the doctor found the issue with the cord, again they explained what they found and asked for permission to take photos, as they had never seen it before.

During the delivery, everything was moving so fast, that I didn’t have time to think. Only afterwards did all of my questions come. The two doctors who were doing my surgery, both came to me afterwards to explain the finding again, as did a consultant, who also tried to help answer my questions. They were great and answered what they could, but it seemed so rare that nobody had seen it before. That was probably what I found most difficult—the lack of experience of it, how did it happen, could it happen again and was it due to in vitro fertilisation……

When I was asked about the possibility of this being written up, I immediately said yes, as all the information I could find on it had negative outcomes. Because of my amazing team, we have a beautiful baby, who is doing well and is happy and healthy, and maybe with more information the next new Mom who this happens to, can have a positive story.

Learning points.

• Fetal movements remain to be an important subjective maternal finding and requires thorough investigation.

• Cord abnormalities remain a significant cause of perinatal death and morbidity.

• Absence of Whartons jelly appears to be a rare finding, with a poorly understood pathophysiology. Further case reports and further study of its development are needed.