Residency · Residency · Obstetrics Gynecology
Breech Presentation: External Cephalic Version and Delivery
Epidemiology and Types
Incidence
Breech presentation occurs in 3 to 4% of term singleton pregnancies. The incidence is much higher at earlier gestational ages, reaching 25% at 28 weeks, but most fetuses convert spontaneously to cephalic presentation by 36 to 37 weeks.
Types of Breech
Frank breech is the most common type, accounting for 65 to 70% of cases. The hips are flexed and the knees extended, with the buttocks presenting and the feet near the head. Complete breech accounts for about 10% of cases, with both hips and knees flexed in a cross-legged position. Incomplete or footling breech makes up 20 to 25% and involves one or both feet or knees presenting below the buttocks. Footling breech carries the highest risk of cord prolapse.
| Type | Frequency | Position | Cord Prolapse Risk |
|---|---|---|---|
| Frank | 65-70% | Hips flexed, knees extended | Lowest |
| Complete | ~10% | Hips and knees flexed | Intermediate |
| Footling (incomplete) | 20-25% | One or both feet presenting | Highest |
Risk Factors for Persistent Breech
Risk factors include prematurity, uterine anomalies such as bicornuate or septate uterus, uterine fibroids (especially in the lower segment), placenta previa, polyhydramnios or oligohydramnios, fetal anomalies (anencephaly, hydrocephalus), multiple gestation, short umbilical cord, prior breech presentation, and nulliparity (due to less uterine laxity).
Diagnosis
Leopold maneuvers reveal a hard, round, ballottable head in the fundus with a soft, irregular presenting part in the pelvis. Ultrasound confirmation determines the type of breech (frank, complete, or footling), estimated fetal weight, amniotic fluid volume, placental location, and any structural anomalies. On cervical exam, a soft irregular presenting part is palpated, and the sacrum, ischial tuberosities, or feet may be identified.
<image>Ultrasound and schematic illustration comparing the three types of breech presentation: frank breech with hips flexed and knees extended, complete breech with hips and knees flexed, and footling breech with one or both feet presenting below the buttocks</image>
External Cephalic Version (ECV)
Indications
ECV is offered for singleton breech presentation at 36 to 37 weeks or beyond. The goal is to convert the fetus to cephalic presentation to allow vaginal delivery and avoid cesarean.
Contraindications
Absolute contraindications include placenta previa or low-lying placenta, active vaginal bleeding, non-reassuring fetal status, ruptured membranes, multiple gestation (except version of the second twin during delivery), hyperextended fetal head, and fetal anomaly incompatible with vaginal delivery. Relative contraindications include oligohydramnios with an amniotic fluid index below 5, intrauterine growth restriction, uterine anomaly, prior cesarean section (not absolute but requiring informed consent), nuchal cord, and obesity (which makes the procedure technically difficult).
Pre-Procedure
Breech presentation is confirmed by ultrasound. A nonstress test confirms fetal well-being. Informed consent is obtained, discussing success rates and risks. The procedure is performed in a setting capable of emergent cesarean. Blood type and screen are obtained, IV access is established, and NPO status is advisable. Tocolysis with terbutaline 0.25 mg subcutaneously 15 to 20 minutes before the attempt relaxes the uterus and improves the success rate.
Technique
The patient is positioned supine with a slight left lateral tilt. Ultrasound guidance is used throughout. The operator identifies the fetal head and breech. The preferred approach is a forward roll: the breech is gently elevated out of the pelvis while the head is guided downward in a forward somersault. If the forward roll fails, a backward roll is attempted. Steady, firm but gentle pressure is applied, avoiding sudden or forceful movements. Multiple attempts may be made if the fetus returns to breech. The fetal heart rate is monitored continuously during and after the procedure. Rh-negative patients receive anti-D immunoglobulin after ECV.
Success Rates and Factors
The overall success rate is 50 to 60%. Factors favoring success include multiparity, transverse lie, adequate amniotic fluid, a relaxed uterus, and a non-engaged breech. Factors associated with lower success include nulliparity, obesity, oligohydramnios, anterior placenta, engaged breech, and frank breech presentation. Approximately 5% of successfully versioned fetuses will revert to breech.
Complications
The most common complication is transient fetal heart rate abnormalities, which are usually self-limited. Placental abruption occurs in less than 1% of cases. Preterm labor, premature rupture of membranes, and cord entanglement are rare. Fetomaternal hemorrhage occurs in 2 to 5%. Emergency cesarean delivery is required in less than 0.5%.
<image>Step-by-step illustration of external cephalic version technique showing the forward roll: the operator's hands elevating the breech from the pelvis with one hand while guiding the fetal head downward with the other, with arrows indicating the direction of rotation, and an ultrasound transducer monitoring fetal heart rate</image>
The Term Breech Trial and Its Legacy
Hannah et al. (2000)
This multicenter randomized controlled trial compared planned cesarean with planned vaginal breech delivery for term frank or complete breech presentations. Perinatal and neonatal mortality and serious morbidity were significantly lower with planned cesarean (1.6% versus 5.0%). No significant difference in maternal morbidity was found. The trial led to widespread adoption of planned cesarean for term breech delivery worldwide.
Criticisms and Subsequent Data
The trial included centers with variable skill and experience in vaginal breech delivery, and many lacked expertise. The 2-year follow-up by Hannah in 2004 showed no difference in neurodevelopmental outcomes. The PREMODA study by Goffinet in 2006 demonstrated that in experienced centers with strict protocols, vaginal breech outcomes were comparable to cesarean. A self-reinforcing cycle has developed in which fewer vaginal breech deliveries leads to fewer trained providers, further reducing the availability of this option.
Current Position
ACOG, SOGC, and RCOG maintain that planned cesarean is the standard recommendation for term breech. However, they acknowledge that vaginal breech delivery may be reasonable in selected cases when performed by an experienced provider. This approach requires institutional commitment to maintaining expertise.
Vaginal Breech Delivery
Patient Selection
Candidates include women with frank or complete breech (not footling, due to high cord prolapse risk), estimated fetal weight between 2,500 and 3,800 g, an adequate maternal pelvis assessed by clinical or imaging pelvimetry, no hyperextension of the fetal head confirmed by ultrasound, gestational age of 37 weeks or more, and no other contraindications to vaginal delivery. An experienced provider must be available and willing, continuous fetal monitoring must be in place, and the ability to proceed immediately to cesarean must exist.
Technique: Assisted Breech Delivery
The breech is allowed to deliver spontaneously to the umbilicus following a hands-off approach until the umbilicus is visible. The Lovset maneuver is used to deliver the arms: the fetal bony pelvis (never the soft abdomen) is grasped, and the trunk is rotated 180 degrees in each direction while applying downward traction. If the arms are extended, the Lovset maneuver or classical arm extraction (hooking a finger over the humerus) is performed. For the aftercoming head, the Mauriceau-Smellie-Veit maneuver places the fetal body on the operator's forearm with two fingers on the malar bones (never in the mouth) while the other hand applies pressure on the occiput to flex the head for controlled delivery. Piper forceps, applied to the aftercoming head, are the gold standard for head entrapment. If the cervix traps the aftercoming head, Duhrssen incisions at the 2, 6, and 10 o'clock positions may be necessary.
<image>Illustration of assisted vaginal breech delivery showing key maneuvers: the Lovset maneuver for arm delivery with the fetus rotated and downward traction applied to the bony pelvis, and the Mauriceau-Smellie-Veit maneuver for the aftercoming head with fingers on the malar bones and flexion pressure on the occiput</image>
Complications of Vaginal Breech Delivery
The most serious complication is head entrapment. Other complications include cord prolapse (especially with footling breech), nuchal arm (arm trapped behind the head), cervical spine injury from excessive traction, brachial plexus injury, and fetal hypoxia from cord compression.
Undiagnosed Breech in Labor
Breech may be discovered only during labor or at full dilation. If the presenting part is advanced and delivery is imminent, vaginal breech delivery may be the safest option. Emergency cesarean remains an option if the breech is not deeply engaged. Every OB/GYN resident must have exposure to breech delivery techniques to manage this scenario.
Clinical Pearls
ECV should be offered to all eligible patients with breech presentation at 36 to 37 weeks or beyond. It is the best strategy to avoid cesarean for breech.
Tocolysis with terbutaline before ECV improves success rates and should be administered 15 to 20 minutes before the attempt.
Nulliparity is the strongest negative predictor of ECV success, but nulliparous women should still be offered the procedure.
In vaginal breech delivery, traction should never be applied to the soft abdomen. The bony pelvis (iliac crests) must always be grasped.
The principle of "hands off the breech" until the umbilicus delivers spontaneously is critical. Premature traction causes arm extension and head entrapment.
Piper forceps for the aftercoming head should be available at every breech delivery because they provide the most controlled delivery.
Every resident needs to learn vaginal breech delivery skills for the undiagnosed breech presenting in advanced labor.
After successful ECV, a nonstress test is performed and the patient is observed for 1 to 2 hours before discharge.
References
- ACOG Committee Opinion No. 745: Mode of Term Singleton Breech Delivery (2018)
- Hannah ME et al. Planned caesarean section versus planned vaginal birth for breech presentation at term: a randomised multicentre trial. Lancet. 2000;356:1375-1383
- Goffinet F et al. Is planned vaginal delivery for breech presentation at term still an option? Results of an observational prospective survey (PREMODA). Am J Obstet Gynecol. 2006;194:1002-1011
- ACOG Practice Bulletin No. 221: External Cephalic Version (2020)
- Hofmeyr GJ et al. External cephalic version for breech presentation at term. Cochrane Database Syst Rev. 2015
- Kotaska A et al. SOGC Clinical Practice Guideline: Vaginal delivery of breech presentation. J Obstet Gynaecol Can. 2009;31:557-566
