Describe external cephalic version — its aetiology, clinical features and management.

Definition

External cephalic version (ECV) is the procedure of converting a non-cephalic (breech or transverse)

Presentation into a cephalic presentation by external manipulation of the fetus through the maternal abdominal

Wall.

Timing and Indications

Performed at 36–37 weeks (before then the fetus often reverts; after, there is little room). It is offered for breech presentation and transverse/oblique lie in an otherwise suitable pregnancy.

Prerequisites

A singleton pregnancy with a non-engaged presenting part and adequate liquor, a reassuring fetal heart, an unscarred uterus, and facilities for emergency caesarean section and fetal monitoring close at hand.

Contraindications

Oligohydramnios or ruptured membranes

, growth restriction or fetal compromise, severe pre-eclampsia, and a known fetal/uterine anomaly.

Technique

Done with ultrasound and fetal-heart monitoring, often under tocolysis (to relax the uterus); the breech is disengaged and the fetus rolled in a "forward somersault". Anti-D is given to Rh-negative women.

A Note on WHY Ecv Is Worth the Trouble

A useful point is understanding why obstetricians go to the trouble of turning a breech baby when a caesarean would be simpler. The calculation is not about this delivery alone but about the woman's whole obstetric future. A successful ECV converts a planned caesarean into a normal vaginal delivery — sparing her the immediate risks of major surgery and, far more importantly, sparing her the uterine scar, which would otherwise commit her to the risks of rupture and abnormal placentation (praevia, accreta) in every subsequent pregnancy. Since ECV succeeds in roughly half of attempts — more with tocolysis, multiparity, adequate liquor and an unengaged breech — offering it to every eligible woman substantially reduces the caesarean rate. Its risks are small but real, which is why it is performed at or after 36–37 weeks (so that, if it precipitates a problem, the baby is mature and can be delivered at once), in a facility with immediate access to caesarean section, with ultrasound guidance and CTG monitoring, tocolysis to relax the uterus, and anti-D afterwards for Rh-negative mothers (because of the risk of fetomaternal haemorrhage). Understanding that ECV trades a small, controlled, monitored risk today against a lifetime of scarred-uterus risk explains why it is recommended.

Success rate is about 50–60% in suitable cases.

• ECV: turning a breech to cephalic by external manipulation, at 36–37 weeks or later — success rate about 50%.
• Performed with ultrasound guidance and CTG monitoring, under tocolysis, in a facility able to perform an immediate caesarean.
• Give anti-D afterwards to Rh-negative women (risk of fetomaternal haemorrhage).
• Contraindications: APH, ruptured membranes, multiple pregnancy, oligohydramnios, fetal compromise/anomaly, a scarred uterus, pre-eclampsia, or any indication for caesarean.
• Complications (uncommon): abruption, cord accident, fetal distress, fetomaternal haemorrhage, rupture of the membranes.

A further point is that success is more likely in a multiparous woman with a lax abdominal wall, adequate liquor, an unengaged breech and a fetus of average size — whereas obesity, engagement of the breech, oligohydramnios and a nulliparous, tense abdomen all predict failure — which is why careful case selection improves the reported success rate.