Cord Prolapse

Introduction

Umbilical cord prolapse is defined as the umbilical cord descending below the fetal presenting part (usually head), through the cervix, in the presence of ruptured membranes. 

Cord prolapse is an obstetric emergency that can quickly lead to fetal hypoxia if left untreated.

Aetiology

The exact cause of cord prolapse varies in each pregnancy, however, generally any factors associated with fetal malposition increase the risk as well as obstetric procedures, these can include:¹

• Breech, transverse, unstable lie
• Twin pregnancy (especially delivery of the second twin)
• Polyhydramnios
• Artificial rupture of membranes
• External cephalic version

Clinical features

History

A history would typically involve clarifying:

• The details surrounding the rupture of membranes (e.g. timing, spontaneous or artificial etc)
• Identification of any potential risk factors (as noted above)

Clinical examination

Typical clinical findings include:²

• Umbilical cord palpated on vaginal examination
• Acute bradycardia/fetal distress (<100 bpm) noted on fetal heart rate monitoring

Less common clinical findings include:

• Umbilical cord visible (hanging outside the introitus)

Investigations

Investigations are rarely required as the diagnosis is based on clinical findings.²

If there is doubt regarding fetal heart rate measurement or fetal position, bedside ultrasound can be used to confirm these.

Management

Cord prolapse is an obstetric emergency as the umbilical cord will develop vasospasm and fetal hypoxia will occur if left untreated.

Vaginal examination allows for confirmation of the diagnosis as well as elevation of the fetal presenting part, preventing pressure on the umbilical cord.

Care should be taken to avoid touching the cord as this will also cause vasospasm.

Filling the bladder can help with the elevation of the fetal presenting part, this can be achieved by inserting a catheter and filling the bladder with 500ml of normal saline.

Maternal position can also help to reduce pressure on the umbilical cord, this is typically the knee-chest position (similar to all fours but with pelvis higher than shoulders).

Immediate delivery is required by caesarean section. If the fetal heart rate pattern is abnormal, this should be a category one caesarean section (delivery within 30 minutes).¹

Complications

Complications of cord prolapse include:

• Birth hypoxia: neonatology team should be present at delivery and paired umbilical cord gases should be taken to assess fetal pH
• Psychological trauma: due to the emergency nature of cord prolapse, the event should be explained to the mother after delivery

Key points

• Cord prolapse is defined as the umbilical cord descending below the presenting part in the presence of ruptured membranes.
• Risk factors include fetal malposition, multiple pregnancy, polyhydramnios and obstetric procedures.
• Management includes elevation of the fetal presenting part by either vaginal examination or filling the bladder.
• Maternal position (knee-chest) can also help prevent pressure on the cord.
• Immediate delivery is required by caesarean section.
• Complications of cord prolapse include birth hypoxia and psychological trauma. 

References

1. Royal College of Gynaecologists. Umbilical Cord Prolapse. 2014. Available from: [LINK]
2. Lawrence Impey & Tim Child. Obstetrics & Gynaecology. 2017.