Cord prolapse has been defined as the descent of the umbilical cord through the cervix alongside (occult) or past the presenting part (overt) in the presence of ruptured membranes. Cord presentation is the presence of the umbilical cord between the fetal presenting part and the cervix, with or without membrane rupture. The overall incidence of cord prolapse ranges from 0.1% to 0.6%. In the case of breech presentation, the incidence is slightly higher than 1%. It has been reported that male fetuses appear to be predisposed to cord prolapse. The incidence is influenced by population characteristics and is higher where there is a large percentage of multiple gestations.
Cases of cord prolapse appear consistently in perinatal mortality enquiries, and one large study found a perinatal mortality rate of 91/1000. Prematurity and congenital malformations account for the majority of adverse outcomes associated with cord prolapse in hospital settings but birth asphyxia is also associated with cord prolapse. Perinatal death has been described with normally formed term babies, particularly with planned home birth. Delay in transfer to hospital appears to be an important contributing factor.
Asphyxia may also result in hypoxic–ischaemic encephalopathy and cerebral palsy. The principal causes of asphyxia in this context are thought to be cord compression and umbilical arterial vasospasm preventing venous and arterial blood flow to and from the fetus. There is a paucity of long-term follow-up data of babies born alive after cord prolapse in both hospital and community settings.
The management of prolapsed cord is one of the labour ward guidelines mandated by the Clinical Negligence Scheme for Trusts (CNST), Welsh Pool Risk and Clinical Negligence and Other Risks Scheme (CNORIS) maternity standards in England, Wales and Scotland, respectively.
The purpose of this guideline is to describe modalities to prevent, diagnose and manage cord prolapse. It addresses those pregnant women at high risk of or with a diagnosis of cord prolapse in hospital and community settings. Pregnancies complicated by fetal malformation or with cord prolapse before 22 completed weeks of gestation ate not covered by this guideline. All later gestations are included.