Breech Presentation

At term, only about 3% of babies have a breech presentation - the babies breech (bottom) presents into the maternal pelvis. Over recent years, there has been increasing interest into the safest method for breech delivery.

 

 

Risks of serious early perinatal morbidity and mortality are three times higher for planned vaginal breech delivery than for elective caesarean section.


Because morbidity and mortality are relatively low, a large number of caesarean sections needs to be performed to avoid a single adverse event.


External cephalic version appears to be a safe procedure that can halve the number of breech presentations but the procedure is not risk-free.


Four guidelines or directives are outlined but need to be adapted to the setting in which they are applied.


Planned vaginal breech delivery is an acceptable choice to offer, provided strict protocols are followed.


 

Can planned vaginal breech delivery be justified?

 

 
Following publication in 2000 of the Term Breech Trial theree has been a major shift toward elective caesarean section for breech delivery at term.^2000-01 This is mainly because of the finding that neonatal mortality and serious morbidity were 5% in the planned vaginal birth group compared with 1.6% in the planned elective caesarean section group.  Although the trial clearly outlines and quantifies the risk, Glezerman^2006-01 has raised concerns regarding the design and methods were serious and raised the case for withdrawing their recommendations. However, there is no prospect of repeating such a large randomised controlled trial to address any of these deficiencies and obstetricians are going to have to decide which method of delivery to offer women. The available information that we can reasonably give to women will have to be sufficient to enable an informed decision to be made on the method of delivery.

There have recently been three large population-based comparative studies from the Netherlands,^2005-01 and Sweden^2005-02 and confirm section has benefits for the baby. However, in a more recent observational prospective study in France and Belgium, the neonatal mortality and morbidity for vaginal breech delivery was 1.6% – this is much lower than in the Term Breech Trial and not significantly different from the caesarean section group.^2006-02

The risk versus benefit aspect needs to be brought into perspective for all obstetric practitioners. Experience, resources and working conditions need to be taken into account. Rietberg et al.^2005-01 calculated that 175 caesarean sections are needed to avoid one fetal death, while Hofmeyr and Hannah^2003-01 suggested that 29 caesarean sections would avoid one case of serious neonatal morbidity or death. There will also, no doubt, be an increase in potential problems, such as uterine scar dehiscence and placenta praevia accreta, in future pregnancies: these are life threatening to mother and baby. In the Rietberg et al. study it was estimated that, for every infant saved by a caesarean section, one woman would experience a uterine rupture during a subsequent pregnancy.

In a large epidemiological study, Smith et al.^2003-02 showed an absolute risk of unexplained stillbirth at or after 39 weeks of gestation of 1.1 per 1 000 women who had a previous caesarean section, compared with 0.5 per 1 000 women who had not. However unlikely such complications are deemed, they must be brought to the attention of the parents when discussing method of delivery and informed consent. In the United Kingdom, 11% of all caesarean sections are now performed for breech presentation, despite guidelines that recommend external cephalic version (ECV).^2003-02

In poorly-resourced health services the benefit of elective caesarean section becomes more dubious. Caesarean section is often performed by relatively inexperienced operators and anaesthetists. This increases the risk to the mother, which may be even greater in the future because of lack of access to facilities for caesarean section in following pregnancies. While clinicians, and the societies who represent them, have drawn up guidelines that are reasonable and sustainable for the conditions in which they practise, they may not be appropriate in other countries.

In their Green-top Guideline No. 20 (April 2001), the Royal College of Obstetricians and Gynaecologists (RCOG) recommended offering all women with an uncomplicated breech presentation an external cephalic version (ECV) at term (37–42 weeks), provided there were no contraindications. If this is not performed, or is unsuccessful, an elective caesarean section at term should be offered. Two important points are highlighted in the guideline: It remains important that clinicians and hospitals are prepared for vaginal breech delivery. Any woman who gives birth to a breech vaginally should be cared for by an attendant with suitable experience.

In December 2006, Guideline No. 20 was updated and divided into two parts, 20a and 20b. This reflects the complex nature of the guideline and that it outlines a less rigid approach to mandatory elective caesarean section, which followed the Term Breech Trial. There is more detailed information on the benefits and risks of planned caesarean section versus planned vaginal breech delivery and on counselling women with a breech presentation. Benefits, risks and the role of ECV are discussed in more detail.

Other important issues addressed are::

Information that should be given about risk to mother and baby in the short and long term for each method of delivery.


Details of intrapartum management of breech presentation and delivery.


Training, skill and experience of the intrapartum attendant.


The need for clear documentation, including details of counselling and the identity of all those involved in the procedures.

American College of Obstetricians and Gynecologists on Breech Delivery

Through their Committee on Obstetric Practice, the American College of Obstetricians and Gynecologists (ACOG) issued a Committee opinion paper on ‘Mode of term singleton breech delivery’ in 2006.^2006-03 This is not as emphatic about elective caesarean section as the earlier RCOG guideline and indicates that planned vaginal breech delivery may be reasonable under hospital-specific protocol guidelines. It emphasises that documented, informed consent, clearly outlining the increased short-term serious risk to the infant, is a essential. The ACOG has produced an excellent patient information sheet, which can be downloaded from their website.

 

Royal Australian and New Zealand College of Obstetricians and Gynaecologists on Breech Delivery

In 2007, The Royal Australian and New Zealand College of Obstetricians and Gynaecologists (RANZCOG) has issued a formal statement concerning breech delivery at term. It indicates that the level of risk is higher in planned vaginal breech delivery than in elective caesarean section but does not exclude vaginal breech delivery as an option. The statement outlines factors that reduce the risk of vaginal delivery and also points out the risk in subsequent pregnancies after caesarean section, including uterine scar rupture and placenta praevia accreta. The final point made is that maternal preference should also be considered.

External Cephalic Version (Breech Version) is discussed on External Cephalic Version

 

Planned vaginal breech delivery

Information regarding risk to the fetus with vaginal breech delivery has been partly quantified by the Term Breech Trial. However, future risk of childbirth after caesarean section, pelvic floor damage and urinary or other incontinence issues after vaginal delivery have not been considered. In the 2-year follow-up study^2004-01 of the children of the women enrolled in the Term Breech Trial, the primary outcomes of death and neurodevelopmental delay at 2 years of age were similar between the two groups. The smaller number of perinatal deaths with planned caesarean section was balanced by a greater number of babies with neurodevelopmental delay. This was unexpected as there had been fewer babies with severe perinatal morbidity in the planned caesarean section group. While inherent neurological abnormality may be the reason for persistent breech presentation, randomisation should have excluded this possible bias.

Planned vaginal delivery thus seems a reasonable alternative to elective caesarean section provided that strict hospital-based protocols are followed, patient selection is carefully supervised and sufficient personnel trained in vaginal breech delivery are available for the delivery. However, training in assessment and delivery of breech presentations must be continued, even if much of it is by simulation with models and video demonstrations.

Training with models and videos must be backed up by observation of experienced obstetricians and closely supervised application in practice. These skills need to be assessed as part of the training programme for registrars. Workshops should be offered for those who are not confident in assessing and performing vaginal breech delivery. Consultants should be available to advise and assist junior staff with vaginal breech assessment, method and timing of delivery. In each unit where vaginal breech delivery is offered, clear protocols and contact personnel need to be documented and continuously audited to help avoid poor outcomes or medicolegal issues.

Women and their partners need to be counselled as to the availability of a suitably experienced person if they request a vaginal breech delivery. If they are not informed of this it may create the basis for litigation, should the outcome be poor. Alternatively, they may feel that elective caesarean section is a safer option in circumstances where appropriate staff members are not always available. Breech deliveries that do occur may, of course, be under unfavourable circumstances, including preterm or advanced labour, where it may not be possible to offer caesarean section. Clearly, complications are more likely to occur, especially if the breech delivery is attended by inexperienced personnel.

 

Elective caesarean section for breech presentation

Since the Term Breech Trial, elective caesarean section at term has been adopted in many parts of the world as the proven delivery method of choice for breech presentation at term. Although criticisms have been raised about the trial, sub-analysis of groups within the trial has resolved many of them, particularly with regard to the short-term fetal outcome. The 2-year neurodevelopmental follow-up is of some concern, as is the risk to the mother in future pregnancies, while the latter has not yet been addressed.

In a secondary analysis of the Term Breech Trial,^2003-01 adverse perinatal outcomes were lowest when prelabour caesarean section was performed and increased with women in labour. Independent risk factors were: labour augmentation, birthweight below 2.8 kg and a long interval between pushing and delivery. The presence of an experienced clinician during vaginal delivery decreased the risk.

A study from Ireland^2002-02 of primigravid women showed that, although the chance of having a breech presentation in the next pregnancy was increased, the overall caesarean section rate was not greater than in women who had had a caesarean section for other indications with cephalic presentation in their first pregnancy. Subsequent occurrence of scar dehiscence and placenta praevia accreta are life-threatening complications and informed consent should include them, even though they may occur in fewer than 1% of cases.

It is wise to document all the risks inherent to either method of delivery and to give women an information sheet outlining these risks, as they may not remember them all. This will help to inform partners or family who may be involved in the decision-making process.

As with all forms of consent, a woman needs to understand the nature of the procedure (competence) and have sufficient information to reach a decision to agree or refuse the procedure (knowledge). Lastly, she must be willing to undergo the procedure with the information she has been given (voluntariness). This informed consent must be clearly and carefully documented. In general terms, women should know about any serious risk that can occur in more than 1% of cases.

The decreased risk to the fetus may sway a woman to choose planned caesarean section on this basis alone. However, should a vaginal breech delivery become necessary through unforeseen circumstances, might she not have grounds for litigation? Clearly, this would depend on the specific circumstances and the accuracy of the information that had been provided about risks of preterm labour, timing of the elective caesarean section and facilities available to accommodate the procedure. Should she choose to have a vaginal delivery after the information has been given, optimal conditions for a vaginal breech delivery, in line with the guidelines, and the presence of a person with sufficient experience to perform the delivery will need to be in place. In many clinical settings this would be difficult to achieve and unless this is made clear to the woman before delivery it may lead to litigation if the outcome is not satisfactory.