Incidence of Cord Prolapse in Breech Presentation
Cord prolapse occurs in approximately 0.4-2.9% of breech presentations at term, with the highest risk in footling breech (up to 11.1% in compound presentations) and significantly lower rates in frank breech presentations.
Overall Incidence Data
The incidence of umbilical cord prolapse varies substantially based on the type of breech presentation and clinical circumstances:
- Frank breech presentation: Approximately 0.4% incidence of cord prolapse 1
- Complete/footling breech: 2.9% incidence, representing a 7-fold higher risk than frank breech 2
- Compound breech presentations: Up to 11.1% incidence, the highest risk category 2
Key Risk Factors That Modify Incidence
The baseline incidence is significantly modified by several clinical factors:
- Prematurity combined with breech: Substantially increases cord prolapse risk beyond the baseline breech-associated risk 2
- Artificial rupture of membranes: Significantly associated with higher cord prolapse rates in breech presentations 3
- Diagnosis in labor: Women diagnosed with breech presentation during labor had the highest cord prolapse rate at 1.4%, compared to 0.4% in those diagnosed antepartum 1
Clinical Context and Detection
The majority of cord prolapse cases (78%) are diagnosed by vaginal examination rather than presenting with obvious cord visibility 3. This underscores the critical importance of:
- Performing vaginal examination immediately after membrane rupture in any breech presentation 3
- Continuous fetal heart rate monitoring to detect occult cord compression 3
- Transvaginal ultrasound screening after 36 weeks can detect cord presentation in approximately 4% of term breech cases, with 86% of detected cases confirmed at cesarean delivery 4
Mortality Implications
When cord prolapse occurs in breech presentation, outcomes are particularly grave:
- 36.2% perinatal mortality rate when cord prolapse complicates breech delivery 2
- The majority of deaths (84%) occur because the fetus is already dead at the time of cord prolapse diagnosis 2
- Corrected perinatal mortality (excluding previable infants <1000g) is 8.6% with prompt cesarean delivery 3
Prevention Strategy
Antepartum screening with weekly transvaginal ultrasound after 36 weeks in breech presentations can identify cord presentation and prevent cord prolapse through planned cesarean delivery 4. In one study, this approach reduced cord prolapse incidence from 4% to 0% (P<0.01) 4.
Critical Pitfall to Avoid
The term "breech presentation" is inadequate for risk stratification—frank breech carries approximately 7-fold lower cord prolapse risk than footling/complete breech, yet these are often grouped together in clinical decision-making 2, 5. Management should be differentiated based on specific breech type, with footling breech warranting immediate cesarean delivery if membranes rupture, while frank breech may allow more time for assessment 5.