Management of the Breech Presentation

1. What every clinician should know


The breech presentation refers to a longitudinal lie where the presenting part is the breech pole, which can be constituted by the fetal buttocks, the thighs and/or the feet. It must be differentiated from a transverse lie, when the feet of the fetus might be extended into the lower uterine segment and cervix. In those cases the fetal head and breech pole would not be found in the uterine fundus but on the maternal flanks.

The vaginal breech delivery has two significant differences relative to the delivery of the fetus in a cephalic presentation:

  • In the vaginal breech delivery the largest segment of dystocia is delivered last (relative to the hips and the shoulders), setting up the potential for mechanical dystocia (particularly soft tissues).

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  • Unlike the delivery in a cephalic presentation, in which the cord is protected until the onset of spontaneous respirations, it has been theorized that in the vaginal breech the appearance of the umbilical cord signals the onset of compression of the cord by the fetal head at the level of the pelvic brim.

These characteristics may potentially result in variable delays in the delivery of the fetal head and therefore in the transition of the fetus to the extrauterine environment. In addition to a higher rate of fetal anomalies and potentially some intrinsic factors to the breech presentation, these differences have been associated with higher rates of neonatal morbidity and mortality when compared to individuals presenting cephalic at the end of their pregnancies.


Depending on what portion of the fetus is presenting, breech presentations have been divided into 3 broad groups:

  • Complete: Buttocks and feet are presenting and usually palpable by vaginal exam of the presentation when the cervix is dilated. It is also recognizable by imaging techniques (X-rays, U/S, CT or MRI)

  • Incomplete: Includes a variety of possibilities involving various degrees of flexion or extension of one or both thighs and one or both lower legs. The most common incomplete breech is called “frank” breech, in which only the fetal buttocks are presenting (both thighs are flexed over the trunk and both lower legs are extended). This can be recognizable by the vaginal exam or imaging techniques.

  • Footling: Only the fetal feet are presenting. This can be recognized by the vaginal examination or imaging techniques. Care must be exerted in calling a footling presentation as the lower legs might be extended from a complete breech presentation.

The diagnostic and guiding point of the breech presentation is the fetal sacrum, palpable as a firm triangle, the base of which is continuous with the fetal spine. Its orientation in the pelvis is described with the guiding point and the corresponding location of the maternal pelvis.

(RSA stands for right sacrum anterior, referring to the location on the pelvis of the guiding point: the fetal sacrum.)

Predisposing factors

The factors contributing to breech presentation can be separated in three large groups, which may coexist:

  • Gestational age (prematurity)

  • Multiple gestations

  • Anomalies (CNS in particular)


Placenta previa

  • Fibroids

  • Uterine anomalies

  • Polyhydramnios

2. Diagnosis and differential diagnosis

Diagnostic criteria

In non-obese patients abdominal palpation may yield enough information regarding the fetal lie and presentation starting at approximately 30 weeks gestation.

On palpation of the lower uterine segment the breech pole is larger, softer and irregular when compared to the cephalic pole (smaller, harder and regular). The breech pole is usually not ballotable.

The digital exam reveals the absence of structures consistent with a fetal head (hard parietal bones, suture and fontanelles) and the presence of a softer ill-defined mass. The palpation of feet (if complete breech) facilitates the diagnosis. The palpation of a chin, nose and orbits will assist in the differentiation of this presentation from a face or brow presentation.

The intergluteal groove can rarely be confused with the sagittal suture. Clinically one of the edges of the intergluteal leads to the fetal gender and anus and finishes in a solid triangle (the fetal sacrum) which is continuous with the fetal spine. The absence of fontanelles and the palpation of the sacrum should alert to the fetal presentation being breech.

Particular care should be taken when palpating to avoid the fetal gender, as repeat examinations have been associated with edema, bruising and, exceptionally, testicular necrosis.

From an imaging standpoint it is important to determine the fetal size, the presence or absence of fetal anomalies, the location of the placenta, the possibility of uterine abnormalities and, if close to term, the flexion of the head. The identification of a loop of cord below the presentation (cord procubitus) is probably worth reporting.

Near term the plane of the fetal face and that of the cervical spine are compared by ultrasound. In the flexed fetus the plane of the face will be parallel to the cervical spine or at an acute angle inferiorly. In the stargazing fetus the plane of the fetal face will be at right angles with the angle of the cervical spine (the plane of the fetal face is perpendicular to the longitudinal axis of the patient).

The assessment of the flexion can also be performed by other imaging modalities (X-ray, CT, MRI) but they are rarely necessary.

  • Abdominal palpation: After 30 weeks in most patients the Leopold maneuvers would assist in the diagnosis of fetal lie (longitudinal; oblique or transverse) and fetal presentation (cephalic or breech). The cephalic pole is smaller, harder and more regular to palpation than the breech pole (softer, larger and irregular).

  • Vaginal examination: With some cervical dilatation the diagnosis of a breech presentation is made with the identification of the sacrum as the guiding and diagnostic point. The palpation of feet would make the difference between a frank breech (no feet palpable), a complete breech (feet and sacrum palpable) or a footling (feet but no sacrum palpable)


Ultrasound and MRI

US and MRI allow for the evaluation of the fetal attitude (and therefore the different modalities of the breech), flexion of the fetal head and its dimensions, and the presence of anomalies potentially associated with the breech presentation.

Differential diagnosis

Oblique or transverse lie. Some fetuses will present as footling breech presentations when the legs are extended in the low uterine segment and cervix. Abdominal palpation and a transabdominal sonogram would provide the correct diagnosis by locating the breech pole.

3. Management


Contraindications to labor include:

  • Funic (cord) presentation.

  • Fetal growth restriction or macrosomia (estimated fetal weight between 2500 and 4000 g).

  • Any presentation other than a frank or complete breech with a flexed or neutral fetal head attitude.

  • Fetal anomaly incompatible with a vaginal delivery.

Labor management

Factors regarded as unfavorable for vaginal breech birth include:

  • Other contraindications to vaginal birth (e.g. placenta previa, compromised fetal condition).

  • Clinically inadequate pelvis.

  • Footling or kneeling breech presentation.

  • Large baby (usually defined as larger than 3800 g).

  • Growth-restricted baby (usually defined as smaller than 2000 g).

  • Hyperextended fetal neck in labor (diagnosed with ultrasound or X-ray where ultrasound is not available).

  • Lack of presence of a clinician trained in vaginal breech delivery.

  • Previous caesarean section.

Decreasing the incidence

Considering the higher morbidity associated with the vaginal delivery of a breech baby, different strategies have been used to decrease the possibility of a breech presentation at delivery. The most important are:

External cephalic version (ECV)
Term pregnancy

The manipulation of the presentation through the maternal abdomen can effectively change the fetal lie from transverse to longitudinal and from breech to cephalic. This is accomplished by one or two operators by identifying the existent lie and exerting gentle external manipulation to slide the fetus within the uterus to adopt a cephalic presentation.

Technique of ECV

The key steps of the procedure are:

  • The elevation of the presentation (to disengage the breech into the abdomen).

  • The compression of the lie (to reduce the size of the fetus and promote flexion of the head).

  • The version.

Much debate has been given whether to use forward or backward flips. Backward flips (towards the fetal spine) promote flexion but may be harder to do.

Contraindications to an ECV


  • Where CD delivery is required for other reasons.

  • Antepartum hemorrhage within the last 7 days.

  • Abnormal EFM tracing.

  • Major uterine anomaly.

  • Ruptured membranes.

  • Multiple pregnancies (except delivery of second twin).

  • Fetal anomalies.

  • Oligohydramnios. The AFI below which the success of ECV is decreased is approximately 10. The success of ECV is approximately 50-60% (40% for nulliparous, and 60% for multiparous women)


  • Small-for-gestational-age fetus with abnormal Doppler parameters.

  • Proteinuric pre-eclampsia.

  • Oligohydramnios.

  • Major fetal anomalies.

  • Scarred uterus. The available data on ECV after one cesarean section are reassuring but are insufficient to confidently conclude that the risk is not increased.

Potential complications include fetal bradycardia (usually transient) or abnormalities in the EFM (approximately 3%), rupture of membranes, abruption placentae, cesarean section for fetal bradycardia and uterine rupture. Rarely fetal fractures have been reported. The risk of undergoing an emergency C/S is approximately 0.5%. About 3% rate of fetuses will revert after a successful version and 3% of the failed ECV will turn spontaneously.

ECV should be performed where ultrasound to enable fetal heart rate visualization, cardiotocography and theatre facilities are available. Cardiotocography should be performed after the procedure. Kleihauer testing is unnecessary but anti-D immunoglobulin is normally offered to Rh(D) negative women. RCOG does not recommend fasting, anesthetic premedication or intravenous access before the versions.

The technique of ECV is facilitated by the use of tocolytics and maternal analgesia (including regional anesthesia). Lubrication of the maternal skin with powder or gel facilitates the external movements. A bedside sonogram can assist in the success of the interventions and to monitor the fetus during the procedure.

In a meta-analysis of the methods contributing to the success of ECV, tocolytics, in particular beta agonists, were effective in increasing cephalic presentations in labor (average risk ratio (RR) 1.38, 95% confidence interval (CI) 1.03-1.85, eight studies, 993 women) and in reducing the number of caesarean sections (average RR 0.82, 95% CI 0.71-0.94, eight studies, 1,177 women).

There were insufficient data comparing different groups of tocolytic drugs. Regional analgesia in combination with a tocolytic was more effective than the tocolytic alone in terms of increasing successful versions (assessed by the rate of failed ECVs, average RR 0.67, 95% CI 0.51-0.89, six studies, 550 women) but there was no difference identified in cephalic presentation in labor (average RR 1.63, 95% CI 0.75-3.53, three studies, 279 women) nor in caesarean sections (average RR 0.74, 95% CI 0.40-1.37, three studies, 279 women).

Results of ECV

A meta-analysis including seven studies and 1,245 women concluded that the use of external cephalic version was associated with a statistically significant reduction in non-cephalic birth (risk ratio (RR) 0.46, 95% confidence interval (CI) 0.31-0.66); and cesarean section (RR 0.63, 95% CI 0.44-0.90). This reduction is in spite of a two-fold increase in intrapartum caesarean sections for successfully turned babies when compared with babies that were not breech at term. This is independent of an increased induction rate: Both fetal and maternal indications for intervention are implicated. A small increase in instrumental delivery is also seen.

Comparing verted and non-verted infants there were no significant differences in the incidence of Apgar score ratings below seven at 1 minute (two trials, 108 women; RR 0.95, 95% CI 0.47-1.89) or 5 minutes (four trials, 368 women; RR 0.76, 95% CI 0.32-0.77), low umbilical artery pH levels (one trial, 52 women; RR 0.65, 95% CI 0.17-2.44), neonatal admission (one trial, 52 women; RR 0.36, 95% CI 0.04-3.24) or perinatal death (six trials, 1053 women; RR 0.34, 95% CI 0.05-2.12).

If an ECV fails a second attempt may lead to a small increase in overall success rates and tocolysis may increase the success rate of a second attempt if it has not been used first. Other methods employed to increase success rates include the application of fetal acoustic stimulation where the back is in the midline, and regional analgesia. For the latter, an increase in success rate is evident with epidural but not spinal analgesia.

Preterm pregnancy

ECV before 36 weeks of gestation is not associated with a significant reduction in noncephalic births or cesarean section. Performing ECV’s at 34-35 weeks versus 37 or more increases the likelihood of cephalic presentation at birth but does not reduce the rate of C/S and may increase the rate of preterm birth. ECV should be offered from 36 weeks in nulliparous women and from 37 weeks in multiparous women. The RCOG recommends performing ECVs from 36 weeks in nulliparous women and from 37 weeks in multiparous women.

Moxibustion and acupuncture

Moxibustion (a treatment method of traditional Chinese medicine) involves the burning of a herb (Artemisia vulgaris) close to the skin to induce a warming sensation. Anecdotal evidence suggests that moxibustion to a certain acupuncture point located at the tip of the fifth toe, may correct breech presentation. The mechanism of action has not yet been determined. Treatment regimens vary and there is no consensus on the best regimen, but moxibustion may be administered for 15-20 minutes, from one to 10 times daily, for up to 10 days. In a meta-analysis of eight trials involving 1,346 women and compared with no treatment, moxibustion was not found to reduce the number of non-cephalic presentations at birth (P = 0.45).

One trial on 226 women by Neri and colleagues evaluated the use of moxibustion plus acupuncture versus no treatment found a reduction of non-cephalic presentation at birth in the treatment group (RR 0.73, 95% CI 0.57-0.94). A meta-analysis of three trials on 470 women moxibustion plus postural technique found a reduction in the number of women with non-cephalic presentation at birth compared with postural technique alone (RR 0.26, 95% CI 0.12-0.56; random-effects analysis, T² = 0.32, I² = 68%).

The authors of these meta-analyses concluded that there is a need for well-designed randomized controlled trials to evaluate moxibustion for breech presentation which report on clinically relevant outcomes as well as the safety.

Postural management (“breech exercises”)

Many postural techniques have been used by midwives, doctors and traditional birth attendants to promote cephalic version. The rationale of these techniques is to promote the natural version of the fetus by relaxing the pelvis in an elevated position. In 1982 Elkins reported on the use of the knee-chest position (15 minutes every two hours of waking for five days). Chenia and colleagues (1987) modified Elkins’s procedure to be used three times a day for seven days with a full urinary bladder. In Bung’s report (1987) women were encouraged to lie down once or twice a day for 10-15 minutes in the supine, head-down position with the pelvis being supported by a wedge-shaped cushion.

In a meta-analysis of the published evidence by Hofmeyr, including 6 studies involving a total of 417 women, the rates for non-cephalic births and Cesarean section were similar between the intervention and control groups (risk ratio (RR) 0.98; 95% confidence interval (CI) 0.84-1.15; RR 1.10; 95% CI 0.89-1.37. The authors concluded that there is insufficient evidence from well-controlled trials to support the use of postural management to decrease the rate of breech presentation at the time of delivery.

Vaginal versus cesarean delivery

Evidence for one route versus the other

A systematic review of randomized trials comparing a policy of intended cesarean delivery (CD) with a policy of intended vaginal birth included three trials with 2,396 participants. Caesarean delivery occurred in 1060/1169 (91%) of those women allocated to planned caesarean section and 550/1227 (45%) of those allocated to a vaginal delivery (VD) protocol. Perinatal or neonatal death (excluding fatal anomalies) or short-term neonatal morbidity was reduced with a policy of planned CD (RR 0.33, 95% CI 0.19-0.56) and perinatal or neonatal death alone (excluding fatal anomalies) was reduced with a policy of planned CD (RR 0.29, 95% CI 0.10-0.86). Most of the data for the review were contributed by the Term Breech Trial (TBT).

After excluding footling or uncertain type of breech presentation at delivery, labors that were induced or augmented with oxytocin or prostaglandins, deliveries associated with prolonged labor and those cases for whom there was no skilled or experienced clinician present at the birth, the risk of the combined outcome of perinatal mortality, neonatal mortality or serious neonatal morbidity with planned CD compared with planned VD was still lower: 16/1006 (1.6%) vs. 23/704 (3.3%) (RR 0.49; CI 0.26-0.91); P = 0.02).

Based on the existing evidence women should be informed that a planned CD carries a reduced composite outcome (perinatal mortality and early neonatal morbidity) for babies with a breech presentation at term compared with planned VB. The magnitude of those risks should be provided.

Mortality was not significantly different (3 of 511 or 0.6%) in the planned vaginal delivery group compared with zero in the planned caesarean group. One of these deaths, included in the intention to treat analysis, occurred before the onset of labor in a cephalic twin weighing 1150 g, highlighting concerns about the adequacy of case selection.

The impact of the trial’s results was due primarily to an excess of short term morbidity in the planned vaginal delivery group. In the TBT, the end point included perinatal mortality and various short term morbidities, including hypotonia, transient brachial plexus injury, and isolated low arterial cord pH or base excess, whose lasting significance is unclear. In countries with low perinatal mortality, this combined end point occurred in 5.7% of planned vaginal deliveries and 0.4% of women undergoing elective caesareans.

On the other hand, couples should also be informed that there is no evidence that the route of delivery influences the long term health of breech-presenting infants delivered at term.

A number of questions were raised following publication of the Term Breech Trial, largely about selection criteria and the conduct of labor.

At that time there was evidence available to indicate that different strategies would eliminate the benefits of planned caesarean section for the baby. Inconsistencies in the care of women in the Term Breech Trial have also been criticized; however, multiple subgroup analyses failed to identify any group for which the benefit of planned caesarean section was eliminated.

For complex phenomena, a large, randomized, multicenter trial does not overrule demonstrated safety. Since publication of the term breech trial, the onus has been placed on individual obstetrical units to retrospectively examine their experience with vaginal breech delivery and to show safety. Several have done so and continue to offer vaginal breech delivery. Safety in these specific centers is due to heterogeneity of human skill, not to statistical anomaly, and vaginal breech delivery in those units should be studied and emulated.

Selection criteria for a vaginal breech birth


  • Willing and cooperative mother.

  • Normal size fetus (2500-4000 g).

  • No congenital anomalies* (relative).

  • Adequate pelvis.

  • No obstetrical contraindications for vaginal delivery.

  • Appropriate setting to perform neonatal resuscitation and a cesarean delivery.

*The vaginal delivery of an anomalous fetus might be the alternative for delivery in cases where fetal survival is not expected (Potter syndrome for example).

Management of a vaginal breech

During labor

Intravenous access is desirable. Oxytocin can be used for augmentation. Continuous electronic fetal monitoring is recommended as these fetuses may require a cesarean delivery for fetal indications. Meconium may appear in the active phase and is a sign of anal patency and compression of the fetal trunk in the birthing canal and not of fetal compromise.

The mother can be transferred to the Delivery Room (or Operating Room) once the presentation is distending the perineum.

Delivery technique

The delivery should ideally take place in the Operating Room with the availability of a Surgical Team, including an anesthesiologist and a surgical technician. A double setup is desirable. A conflict exists between the need to deliver the baby rapidly to avoid progressive acidosis and the need to avoid trauma due to a hasty delivery. It has been speculated that progressive acidosis during the period from exposure of the umbilical cord to delivery of the aftercoming head may be reduced by expediting the cord-to-head delivery time to occur during a single contraction. At this time there is not enough evidence to evaluate the effects of expedited vaginal breech delivery.

The keys to a successful vaginal delivery of a fetus in breech presentation are:

  • Good maternal positioning in the delivery bed (enough clearance is needed in front of the perineum to effect downward traction of the presentation).*

  • Avoid pulling the presentation until the delivery of the cord insertion.

  • The creation of a loop of cord to facilitate the rest of the delivery (by gentle downward traction on the visible cord).

  • The appropriate obstetric manipulation of the fetal long bones (flexion or stabilization of joints as appropriate).

  • The appropriate placement of the hands for the manipulation of the fetal trunk (on the fetal iliac wings, not the fetal ribs or lumbar muscles).

  • The gentle downward traction of the fetal trunk between delivery of segments of dystocia (hips and shoulders and between shoulders and head) to promote head flexion.

  • The constant communication with the delivering mother (to provide feedback and direct pushing efforts when needed).

  • The availability of forceps for the possibility of assisting the delivery of the aftercoming head.

  • The availability of supporting personnel including a Pediatric/Neonatal Team proficient in resuscitation, should assistance in the neonatal transition be required.

  • Good documentation in the form of a predelivery note (including the assessment of the fetus, maternal pelvis and informed consent) and a delivery note describing the maneuvers employed.

*If delivery is occurring imminently on a labor or hospital bed, rather than attempting to move the patient to a delivery area, assisting turning the patient 90 degrees so that she is perpendicular to the bed might be the fastest way to prepare for the vaginal delivery of a breech.

Use of forceps

Piper forceps, Laufe forceps or Kielland forceps can be used to assist the delivery of the aftercoming head on a breech. Their presence in the delivery room is recommended. Most fetuses in breech presentation would be in the equivalent of an occipito anterior presentation. The forceps application is a direct anterior with the operator standing (or kneeling) under the presentation.

The utilization of forceps requires an assistant to hold the fetal trunk and limbs to allow the obstetrician to place forceps blades. During this maneuver attention needs to be made not to elevate the fetal body beyond the horizontal plane as this elevation could promote deflexion and make the forceps application and the fetal extraction more difficult.

After locking the blades the fetus can be laid on the forceps shanks to complete the delivery. The mechanism of delivery of the fetal head in a breech (unlike that of most cephalic presentations) is by flexion and the forceps needs to be elevated slightly.

Special situations

Preterm infant

The preterm infant offers additional difficulties for the vaginal breech delivery. These are related to the higher head to body ratio when compared to a term infant, which facilitates not only a descent of the presentation through a partially dilated cervix but also contributes to potential head entrapment.

Previous cesarean section

A breech presentation is not an absolute contraindication for a trial of labor and a vaginal birth after cesarean section. In this case the same conditions and precautions employed for the VBAC and for the breech presentation apply. An informed consent detailing both the risks of a trial of labor and a vaginal breech delivery is required.

Second twin

Non-cephalic presentation of the first twin (twin A), the second twin (twin B) or both twins occurs in about 60 % of all twin pregnancies.

The route of delivery of dichorionic diamniotic or monochorionic diamniotic is subject of controversy. According to the results of a Spanish study vaginal delivery is as safe as elective cesarean section in twin pregnancies when the first twin is in cephalic presentation and the intrapartum management should not vary due to chorionicity. One high-quality clinical trial (60 twin pairs) and 16 moderate/low-quality observational studies (3,167 twin pairs) showed no difference in neonatal outcome between vaginal and cesarean delivery in twin A and/or B. No final conclusion could be drawn by the authors of the meta-analysis due to the small sample sizes and statistic limitations of the included studies. Randomized studies with sufficient power are required to make a strong recommendation.

Increasing twin-to-twin delivery time does not seem to be associated with adverse fetal outcome. Expectant management of the second twin appears possible and elapsed time alone does not appear to be an indication for intervention.

4. Prognosis and outcome

Neonatal outcomes
Short term

They include intracranial associated with tentorial tears, rupture of the liver or spleen, and fracture dislocation of the cervical spine. The manipulation of trunk and limbs in breech delivery may cause muscle damage, sometimes severe and associated with intramuscular coagulation, and there may also be evidence of the crush syndrome in other organs.

Long term

The incidence of minor childhood handicap following breech presentation has been found to be high (19.4%) and similar for those delivered following trial of labor and those following an elective caesarean section.

5. Training

Teaching vaginal breech delivery techniques to residents, fellows and other providers, including midwives and family physicians, should be an important educational task from academic institutions with simulation capabilities. For practitioners with active obstetrical practices encountering a breech presentation in labor is almost unavoidable.

The cognitive skills required to counsel woman, indicate and perform an ECV, manage labor, and deliver the fetus should be provided as a bundle of comprehensive breech presentation management.

6. What is the evidence for specific management and treatment recommendations

Hofmeyr, GJ, Kulier, R. “Cephalic version by postural management for breech presentation”. Cochrane Database of Systematic Reviews. 2012. pp. CD000051

Bung, P, Huch, R, Huch, A. “Is Indian version a successful method of lowering the frequency of breech presentations?”. Geburtshilfe und Frauenheilkunde. vol. 47. 1987. pp. 202-5.

Chenia, F, Crowther, CA. “Does advice to assume the knee-chest position reduce the incidence of breech presentation at delivery? A randomized clinical trial”. Birth. vol. 14. 1987. pp. 75-8.

Coyle, ME, Smith, CA, Peat, B. “Cephalic version by moxibustion for breech presentation”. Cochrane Database of Systematic Reviews. 2012. pp. CD003928

Neri, I, Airola, G, Contu, G, Allais, G, Facchinetti, F. “Acupuncture plus moxibustion to resolve breech presentation: a randomized controlled study”. Journal of Maternal-Fetal and Neonatal Medicine. vol. 15. 2004. pp. 247-52.

Hofmeyr, GJ, Kulier, R. “Expedited versus conservative approaches for vaginal delivery in breech presentation”. Cochrane Database of Systematic Reviews. 2012. pp. CD000082

Hofmeyr, GJ, Kulier, R. “Expedited versus conservative approaches for vaginal delivery in breech presentation”. Cochrane Database of Systematic Reviews. 2012. pp. CD000082

Hofmeyr, GJ, Kulier, R. “External cephalic version for breech presentation at term”. Cochrane Database of Systematic Reviews. 2012. pp. CD000083

Cluver, C, Hofmeyr, GJ, Gyte, GML, Sinclair, M. “Interventions for helping to turn term breech babies to head first presentation when using external cephalic version”. Cochrane Database of Systematic Reviews. 2012. pp. CD000184

Collins, S, Ellaway, P, Harrington, D, Pandit, M, Impey, L. “The complications of external cephalic version: results from 805 consecutive attempts”. BJOG. vol. 114. 2007. pp. 636-8.

Nassar, N, Roberts, CL, Barratt, A, Bell, JC, Olive, EC. “Systematic review of adverse outcomes of external cephalic version and persisting breech presentation at term”. Paediatr Perinat Epidemiol. vol. 20. 2006. pp. 163-71.

Hutton, E, Hannah, M, Ross, S, Delisle, M, Carson, G. “for the Early ECV2 Trial Collaborative Group The Early External Cephalic Version (ECV) 2 Trial: an international multicentre randomised controlled trial of timing of ECV for breech pregnancies”. BJOG. vol. 118. 2011. pp. 564-77.

Kayem, G, Goffinet, F, Clement, D, Hessabi, M, Cabrol, D. “Breech presentation at term: morbidity and mortality according to the type of delivery at Port Royal Maternity hospital from 1993 through 1999”. Eur J Obstet Gynecol ReprodBiol. vol. 102. 2002. pp. 137-42.

Giuliani, A, Schoell, W, Basver, A, Tamussino, K. “Mode of delivery and outcome of 699 term singleton breech deliveries at a single center”. Am J Obstet Gynecol. vol. 187. 2002. pp. 1694-8.

Alarab, M, Regan, C, O’Connell, MP, Keane, DP, O’Herlihy, C. “Singleton vaginal breech delivery at term: still a safe option”. Obstet Gynecol. vol. 103. 2004. pp. 407-12.