Why use more retrospective data and modelling to support universal third trimester scanning when prospective data suggests the implementation of specialist vaginal breech birth teams is equally likely to impact outcomes?

Investing in staff and their skill development will achieve the same, if not better, results and should be the priority.

This a response to a recently published report in PLOS Medicine suggesting that implementation of universal third trimester ultrasound scanning in pregnancy improves outcomes for babies and mothers.

The following contributors have approved this expression of concern:

Researchers and Clinicians:

  • Shawn Walker, Researcher in Residence and Honorary Consultant Midwife, Imperial College Healthcare NHS Trust
  • Emma Spillane, Deputy Director of Midwifery and OptiBreech Lead, Kingston Hospital NHS Trust, London
  • Sabrina Das, Consultant Obstetrician and OptiBreech Lead, Imperial College Healthcare NHS Trust
  • Philippa Corson, Consultant Obstetrician and Breech Clinic Lead, Royal London Hospital, Barts Health NHS Trust
  • Susan Bewley, Emeritus Professor of Obstetrics & Women’s Health, King’s College London

OptiBreech Patient and Public Involvement Leads:

UK researchers have an ethical obligation to involve service user groups in design and interpretation of research studies
  • Siân Davies
  • Nimisha Johnstone

Norfolk and Norwich University Hospital Maternity Voices Partnership Service User Representatives:

  • Lisa Brophy
  • Marion Frey-Alqurashi
  • Rachel Graveling
  • Siobhan Ridley
  • Evelyn Shadlock

Knights et al1 confidently demonstrate that routine third trimester, including point-of-care ultrasound (POCUS) performed by midwives, can significantly reduce undiagnosed breech presentation in labour. This is welcome, as women find diagnosis of breech presentation in labour traumatic, regardless of the outcome.2 Although the considerable psychological impacts were not discussed, all should support the plan to increase safety, choice and personalised care through better antenatal detection of breech presentation.

However, the authors then assert that, “Short-term adverse perinatal outcomes, including [neonatal unit] admission and low Apgar scores, were significantly lower for the pregnancies with diagnosed breech presentation at term following a policy for screening by either routine third trimester scan or POCUS.”  This was despite no evidence given that any neonatal outcome achieved a statistically significant improvement. Indeed, hypoxic ischemic encephalopathy (HIE) increased from 0.3% to 0.4% in the St Georges University Hospital (SGH) cohort. The authors then ran Bayesian log-binomial regression models mostly using data from a previous evaluation of the same intervention on a different population (Salim et al),3 falsely concluding that there was a high probability the intervention would reduce adverse outcome rates.

Oxford’s implementation data

The publicly available data for the Salim et al study (S1 Data. Study data set)3 indicate that eight cases of serious neonatal morbidity (HIE and/or death) occurred:

Case numberPresentation at birthGestation at birthMode of birthScan after 35 weeks?Seen in breech clinic?Before or after universal USSPreventable with universal scanning?
4343Cephalic (after ECV)42+2VCYesYes (+ECV)BeforeNo
19867Cephalic (after ECV)42+2VentouseYesYes (+ECV)AfterNo
Key: * = death, ECV = external cephalic version, VB = vaginal breech birth, EMC = emergency caesarean birth, VC = vaginal cephalic birth

In six (75%) Oxford cases, the breech presentation was identified antenally. In 1/2 (50%) undiagnosed cases, a presentation scan would not have prevented the breech labour, which occurred at 37+2 weeks gestation. In both cases of death, the breech had been diagnosed clinically and the women had been seen in breech clinic. In two additional diagnosed cases, the breech service worked exactly as it was intended; two successful ECVs were performed. Nonetheless, HIE occurred following these cephalic births.

The total potential benefit in Oxford was a reduction of two cases of HIE and two less NICU admissions with Apgar <7 at 5 minutes without HIE, i.e. 44 versus 40 neonatal composite adverse outcomes in 1052 third trimester breech presentations, at a cost of 7,673 additional scans and 65 additional ECV procedures. 

Norwich charity funding

Knights et al1 do not explain that Norfolk and Norwich University Hospital (NNUH) spent £100,000 of NNUH Hospitals Charity funding4 on handheld ultrasound scanners. The results in their cohort (Table 4) indicate two fewer neonatal admissions and one less case of Apgar score <7 at 5 minutes after implementation. Neither of these would have been considered a serious adverse outcome in the Term Breech Trial5 nor PREMODA study.6 Thus, there is no causative evidence of improvement, nor is this strategy is likely to prove cost-effective for implementation at scale.

St Georges’ specialist service

Knights et al failed to even look for confounding factors, let alone control for them – a serious source of bias in retrospective studies (see item 7 in the STROBE checklist, ‘Variables’).7 Yet, during their study time frame, and known to the authorship team, SGH also participated in a prospective multi-centre evaluation of physiological breech birth training, the results of which were already published in 2021.8 Both Knights and Mattiolo report a similar number of vaginal breech births, 64 (49 before and 15 after) and 90 (37 before and 53 after) respectively. Mattiolo et al also report outcomes for actual vaginal breech births. Among births where there was no attendant who had completed the enhanced training present, the severe neonatal composite adverse outcome rate was 5/69 (7.2%). Among births attended by someone who had completed the enhanced training, in the same settings, it was 0/21 (0%).

Between 2017-2020, overlapping with the implementation of the scanning programme, a specialist clinic and intrapartum care service for women requesting a vaginal breech birth were implemented at SGH.9  After 100 doctors and midwives had received a whole day’s training, the internal guideline was updated to include a physiological breech management algorithm.10 This was incorporated into monthly mandatory training to all staff, introducing substantial changes to vaginal breech birth practice. All obstetric trainees received half-day training. New joiners received the whole-day training repeated 6-monthly. By 2019, the rate of planned VBB had increased from 1.3% to 12.3% of all births in breech presentation.11 Internal audit of this service demonstrated substantial reduction in the emergency caesarean birth rate, from 42.9% to 24.8% of all births in breech presentation.11

The specialist service at SGH was discontinued when the breech specialist midwife (Spillane) relocated in 2020 and was not replaced. Nevertheless, the potential confounding effects need to be considered. When services invest in staff skill development, those effects extend beyond each individual birth.12

Oxford’s breech team

from the Oxford University Hospitals NHS Foundation Trust website, https://www.ouh.nhs.uk/maternity/antenatal/care/specialist/

A specialist intrapartum service was also implemented at Oxford during the Salim et al. study,13 with the ‘dedicated on-call team’ for vaginal breech births publicly advertised on the hospital website.14 This is a significant difference in practice compared to most NHS units (except OptiBreech sites). Among the breech presentations >37 weeks with labour, planned vaginal breech births increased from 7.4% (12/162) to 17.6% (21/98) after the introduction of universal scanning. The provision of this team also appeared to improve the safety of the actual vaginal breech births that occurred.

 Admission to NNUApgar <7 at 5HIEPerinatal mortality
Planned VBB2/16 (12.5%)0/16 (0%)0/16 (0%)0/16 (0%)
Unplanned VBB7/42 (16.7%)3/42 (7.1%)5/38 (13.2%)2/42 (4.8%)
Secondary analysis of publicly available data from Salim et al

The differences between planned and unplanned VBB are comparable to Mattiolo et al.8 Could the authors use these data in Bayesian log-binomial regression models to demonstrate the beneficial effect of implementing breech birth teams? We cannot assume that similar results would occur in settings that do not offer a similar service. 


The opportunity to access a third trimester presentation scan remains important, especially for women planning an out-of-hospital birth. But women find it psychologically distressing and dehumanising to be unable to access skilled support for a vaginal breech birth, both antenatally and in labour.15–17 Unless an evidence-based plan for improving this support is in place, matters will never change. When we prospectively evaluated the implementation of breech teams,15 one in five participants transferred from their original booking hospital to access supportive care for a vaginal breech birth.18 Some of these women came from SGH (since this VBB service is no longer available) and NNUH (approximately three hours car drive from the nearest OptiBreech site). Further unanticipated risks are introduced for women whose babies are diagnosed as breech but who cannot access their preferred mode of birth locally. More inequalities are created among women for whom the required travel and self-advocacy is impossible.

Determining which interventions improve clinical and cost-effectiveness outcomes for term breech pregnancies requires properly powered, prospectively registered, randomised controlled trials with publicly available, pre-specified protocols and anonymised data sets. It is extraordinary that £100,000 of charitable money was spent on equipment alone, outside the context of carefully planned research, and without service user involvement in priority setting. This has merely resulted in a poor-quality publication and plenty of mass media soundbites.4,19,20 Currently, many NHS sites lack the funding for trained staff to offer all needed care options (ECV, VBB and ELCB) that are currently recommended in RCOG21 and NICE guidelines.22,23 Investing in staff and their skill development will achieve the same, if not better, results and should be the priority.


  1. Knights S, Prasad S, Kalafat E, et al. Impact of point-of-care ultrasound and routine third trimester ultrasound on undiagnosed breech presentation and perinatal outcomes: An observational multicentre cohort study. PLoS Med. 2023;20(4):e1004192. doi:10.1371/journal.pmed.1004192
  2. Lightfoot K. Women’s Experiences of Undiagnosed Breech Birth and the Effects on Future Childbirth Decisions and Expectations. DHealthPsych. University of the West of England; 2018. http://eprints.uwe.ac.uk/33278
  3. Salim I, Staines-Urias E, Mathewlynn S, Drukker L, Vatish M, Impey L. The impact of a routine late third trimester growth scan on the incidence, diagnosis, and management of breech presentation in Oxfordshire, UK: A cohort study. Myers JE, ed. PLoS Med. 2021;18(1):e1003503. doi:10.1371/journal.pmed.1003503
  4. Norfolk and Norwich University Hospitals NHS Foundation Trust. Extra pregnancy scan significantly reduces the number of breech births, new research shows. Website. Published 2023. Accessed April 16, 2023. https://www.nnuh.nhs.uk/news/extra-pregnancy-scan-significantly-reduces-the-number-of-breech-births-new-research-shows/
  5. Hannah ME, Hannah WJ, Hewson SA, Hodnett ED, Saigal S, Willan AR. Planned caesarean section versus planned vaginal birth for breech presentation at term: a randomised multicentre trial. The Lancet. 2000;356(9239):1375-1383. doi:10.1016/S0140-6736(00)02840-3
  6. Goffinet F, Carayol M, Foidart JM, et al. Is planned vaginal delivery for breech presentation at term still an option? Results of an observational prospective survey in France and Belgium. Am J Obstet Gynecol. 2006;194(4):1002-1011. doi:10.1016/j.ajog.2005.10.817
  7. Vandenbroucke JP, Von Elm E, Altman DG, et al. Strengthening the Reporting of Observational Studies in Epidemiology (STROBE): explanation and elaboration. PLoS Med. 2007;4(10):1628-1654. doi:10.1371/JOURNAL.PMED.0040297
  8. Mattiolo S, Spillane E, Walker S. Physiological breech birth training: An evaluation of clinical practice changes after a one‐day training program. Birth. 2021;48(4):558-565. doi:10.1111/birt.12562
  9. Spillane E, Walker S. Case study supporting continuity of care models for breech presentation at or near term. Pract Midwife. Published online 2019:36-37.
  10. Spillane E, Winstanley C, Swer M. Breech. St George’s Hospital Practice Guideline; 2019.
  11. Spillane E. St George’s Breech Clinic – Results. In: Physiological Breech Birth Training [Online]. Breech Birth Network; 2020. Accessed April 18, 2023. https://vimeo.com/486516151
  12. Walker S, Parker P, Scamell M. Expertise in physiological breech birth: A mixed-methods study. Birth. 2018;45(2):202-209. doi:10.1111/birt.12326
  13. Ord C. John Radcliffe midwife, Anita Hedditch, shortlisted for national award | Oxford Mail. Oxford Mail. https://www.oxfordmail.co.uk/news/17420964.john-radcliffe-midwife-anita-hedditch-shortlisted-national-award/. Published February 9, 2019. Accessed April 16, 2023.
  14. Oxford University Hospitals. Specialist antenatal clinics – Maternity. Website. Published 2023. Accessed April 16, 2023. https://www.ouh.nhs.uk/maternity/antenatal/care/specialist/
  15. Dasgupta T, Hunter S, Reid S, et al. Breech specialist midwives and clinics in the OptiBreech Trial feasibility study: An implementation process evaluation. Birth. 2022;00:1-10. doi:10.1111/birt.12685
  16. Morris SE, Sundin D, Geraghty S. Women’s experiences of breech birth decision making: An integrated review. Eur J Midwifery. 2022;6(January):1-14. doi:10.18332/EJM/143875
  17. Petrovska K, Watts NP, Catling C, Bisits A, Homer CS. ‘Stress, anger, fear and injustice’: An international qualitative survey of women’s experiences planning a vaginal breech birth. Midwifery. 2017;44(0):41-47. doi:10.1016/j.midw.2016.11.005
  18. Walker S, Spillane E, Stringer K, et al. The feasibility of team care for women seeking to plan a vaginal breech birth (OptiBreech 1) – an observational implementation feasibility study in preparation for a pilot trial. BMC Pilot & Feasibility Studies. 2023;In Press.
  19. Hall R. Third scan could greatly reduce UK breech birth numbers. The Guardian. Published April 7, 2023. Accessed May 1, 2023. https://www.theguardian.com/society/2023/apr/06/third-scan-reduce-uk-breech-birth-numbers-study-suggests
  20. Pickles K. Third scan could cut breech births by 70%. The Daily Mail. Published April 7, 2023. Accessed May 1, 2023. https://www.mailplus.co.uk/edition/health/270217/third-scan-could-cut-breech-births-by-70?collection=16684
  21. Impey L, Murphy D, Griffiths M, Penna L, on behalf of the Royal College of Obstetricians and Gynaecologists. Management of Breech Presentation. BJOG. 2017;124(7):e151-e177. doi:10.1111/1471-0528.14465
  22. NICE. Intrapartum care for women with existing medical conditions or obstetric complications and their babies. Evidence review for breech presenting in labour. NICE guideline [NG121]. NICE. Published 2019. https://www.nice.org.uk/guidance/ng121/resources/intrapartum-care-for-women-with-existing-medical-conditions-or-obstetric-complications-and-their-babies-pdf-66141653845957
  23. NICE. Antenatal Care.; 2022. Accessed November 29, 2022. https://www.nice.org.uk/guidance/ng201

BICS2022 Conference

The OptiBreech Research and Public Involvement team share their work at the #BICS22 conference.

The OptiBreech Team enjoyed meeting each other in person for the first time at last week’s British Intrapartum Care Society Conference. And we won a prize! We are so grateful to the women who have participated in our research, the Principal Investigators who have made it all happen locally, and our Steering Committee. Here’s what we shared at the conference:

Dr Siddesh Shetty and Dr Shawn Walker

Is it feasible to test OptiBreech Care in a clinical trial?: results of the OptiBreech 1 study – Dr Shawn Walker, Tisha Dasgupta, Siân Davies, Sarah Hunter, Phoebe Roberts, Prof Jane Sandall, Prof Andrew Shennan. We shared the results from our first-stage study, OptiBreech 1. We are currently writing these up in publication format and will share as soon as that is ready. This presentation won the top oral abstract prize at the conference.

The roles and responsibilities of breech specialist midwives in the OptiBreech Care Trial feasibility study: a qualitative inventory Davies, Dasgupta, Natasha Bale, Alexandra Birch, Walker. Siân Davies shared a poster about the role of Breech Specialist Midwives, as described by midwives and obstetricians participating in OptiBreech 1.

Toolkit for implementing breech clinics and specialist midwives to support planned vaginal breech births – OptiBreech PPI Lead and Service User Representative Phoebe Roberts presented this poster. Read more about it here.

Ritika Roy and Cecelia Gray

Women seek ‘connected autonomy’ when they wish to plan a vaginal breech birth at term: a systematic review and meta-synthesis – Ritika Roy, Cecelia Gray, Charlene Prempeh, Walker. Medical students Roy and Gray presented the results of their 2021 King’s Undergraduate Research Fellowships. The results are ready for publication and will be shared in that format soon!

Not too fast not too slow: the legacy of time management in vaginal breech births Jacana Bresson, Walker. Midwifery student Bresson presented the results of her review of obstetric texts in the Royal College of Obstetricians and Gynaecologists and Wellcome Trust Libraries, funded by a 2022 King’s Undergraduate Research Fellowship.

Assessing feasibility of economic evaluation alongside a full trial for ‘OptiBreech Care’ with development and testing of a decision model to assess its long-term cost-effectiveness Dr Siddesh Shetty, Dr Shawn Walker, Prof Julia Fox-Rushby. The Health Economics team used this as an opportunity to gain feedback and peer review on the economic model developed.

Thanks also to the BICS Committee, who organise a wonderful, supportive, multi-disciplinary conference every time!

Specialist midwives and clinics – inviting your views

Help us get it right, Wednesday 19th January 2022, 12:00-13:00. Are we accurately reflecting your views on breech specialist midwives and clinics?

We would like to invite women, birthing people and their families who have experienced a breech pregnancy at term to attend an online focus group discussion on Wednesday 19th January 2022, 12:00-13:00 to be conducted via Microsoft Teams.  Anyone with an interest and experience of breech pregnancy can participate.

The purpose of this meeting will be to get your perspective on the work we have been doing so far.

We have been working on analysing data from qualitative interviews held with OptiBreech 1 participants. To date, we have interviewed 15 women purposefully sampled to reflect various OptiBreech sites, mode of births, and outcomes. Our main objective was to understand what makes the OptiBreech intervention acceptable (or not) to women.

The key themes that we have found are:

  1. Access to skilled breech care: Vaginal breech birth as a viable and safe option is still unknown to many, and lack of specialists reduced equity of access. Women who were referred to a specialist at one of the OptiBreech sites or were already receiving care at a study site found it easy to access and participate in their care. Women who had to transfer care from another hospital or find an OptiBreech site themselves had a difficult time doing so, often requiring increased effort, multiple trips, time off work etc. 
  1. Balanced information: Women really appreciated being provided balanced information on the safety and risks of vaginal breech birth vs. caesarean section including possible complications and how to manage them. This enabled them to make autonomous informed decisions and increased self-efficacy and confidence, not only in themselves but also in the breech specialist midwife. Conversely, when women had to do this research themselves because they were not getting cohesive information from the healthcare professionals, this was seen as a burden and sometimes women were made to feel pressure to choose caesarean section as the ‘safe’ choice. 
  1. Shared responsibility: Women often felt emotional burden including feelings of stress, judgement, and guilt because of the choices they had made to have a vaginal breech birth, both from family and friends, as well as other healthcare professionals. Speaking with and being cared for by the OptiBreech specialist midwife helped ease this emotional burden and gave the women confidence in their choices.
  1. Team dynamics: We found that women had placed an enormous amount of trust and confidence in the breech specialist midwife which extended to the rest of the team, attributed to previous experience, skills and knowledge. Although women did not know all the members of the team, the trust and confidence was extended to them because of shared responsibility and training requirements needed by all OptiBreech team members.

We need your input on our findings and invite your opinions on whether these findings are relevant to you, if we have interpreted them correctly, or if we have missed any important factors in what makes OptiBreech an acceptable intervention. At the meeting we will present a short summary of our findings so far, and then have an open discussion to hear any thoughts, opinions, or questions you may have.

The meeting will be held on Wednesday 19th January 2022, 12:00-13:00 via Microsoft Teams.  

Join on your computer or mobile app  

Click here to join the meeting  

PPI: proposal development phase

While I was developing this proposal, I sought input from service users in several ways:

Ensuring good information

The importance of complete and understandable information about the feasibility trial and about the option of vaginal breech birth was echoed across feedback from all sources. This has been highlighted as the main ethical issue in the Detailed Research Plan.

As the protocol develops, I will engage carefully with those who have indicated an interest in remaining involved in the feasibility study to ensure information meets women’s needs. My colleague Emma Spillane, breech midwife at St George’s Hospital in London, has been developing an information leaflet about options for breech a term. This includes infographics, which women with autism and information processing challenges have fed back is very helpful. I will build on this for the feasibility study.

We will also look carefully at the number of women who are not able to participate in the trial because of informational barriers, such as the inability to understand written English. This will help to understand what translation services, into what languages, we may need to make use of in a full trial to enable equity of participation and access.

Lay reviewers from the RDS London Fast Track Service expressed concern about the legal situation should an adverse outcome occur with a vaginal breech birth. Women in both arms of the trial will be able to choose their preferred mode of birth. The difference is: women under physiological breech birth care will be offered assurance that, if they choose to plan a vaginal breech birth, the team will do everything possible to ensure they are attended by someone who is trained, skilled and experienced in physiological breech birth. In many NHS Trusts, the availability of such support is uncertain, as it depends on who is on shift in the labour ward on any given day/night. Women will be counselled as per the RCOG guideline and local guidelines regardless of their group allocation. They will be informed that we are doing this trial because the available evidence indicates that the physiological breech birth approach may improve access to and outcomes of vaginal breech births, but that we are not certain – hence the need for the research.

Will women participate in this research?

Designing a trial that would produce useful information for women, using methods that were acceptable to women participating in the research, was an important priority to me. The Term Breech Trial46experienced recruitment difficulties, which may have influenced the results.35 Early feedback moved the trial design in a more pragmatic direction, to a design that enables women to have the final say in whether they have an ECV and how they give birth to their breech baby. Another benefit of this design is that it will enable us to study how this new model of care influences women’s perception of the choices available to them.

When we asked those who attended the MVP meeting how many women out of 10 they thought would agree to participate, the range of answers was 5-8, with an average of 6.66. To increase enrolment, MVP members recommended a second recruitment opportunity immediately prior to any scheduled ECVs. This will give women time to think about it, and research midwives ability to identify potential candidates who may not have been offered the opportunity to participate immediately following their scan. This has been incorporated into the trial protocol.

One concern was that all women who participate would want specialist care, and would be disappointed if randomised to standard care. Although making specialist care unavailable outside of the trial is necessary for this design to succeed, and there was general agreement and understanding about this, some women felt it was unfair. For this reason, when a decision is made about whether to proceed to a full trial, we will consider whether randomisation at the individual level has worked. We will compare this to feedback from Trusts who indicate a willingness to participate in a full trial. Following the completion of the feasibility study, we will consider whether the current design will work. If not, and if enough Trusts are keen to participate, another design may be more appropriate, such as a stepped wedge cluster randomised controlled trial. In this type of research, individual Trusts would be randomised to implement physiological breech birth care at different times, rather than individual women.

What about the women who have had negative experiences of breech birth? Or those who are happy with standard care?

Women who respond to a call for involvement in development of a breech birth trial are more likely to have had either positive experiences of breech birth or negative experiences finding a lack of experienced support, for either planned or unplanned breech births.

Thank you to Maureen Treadwell of the Birth Trauma Association for helping me ensure this proposal is informed by the experiences of women who have felt traumatised by not being able to plan a vaginal breech birth, as well as those who have felt traumatised after planning a breech birth that did not go to plan. Women who have had negative experiences of breech birth may be more reluctant to engage in discussions about a breech trial, for very good reasons. Service user advocates like Maureen, who listen carefully to the stories of many women across the UK, help these voices to be heard as we strive to Do No Harm.

Maureen and the BTA highlighted that the goal of any further breech research should be to increase the quality of information and the availability of choice for women carrying a breech baby at term, rather than as part of a strategy that to reduce the CS rate.

This resonated with feedback from the RDS London Fast Track Review Service, through which four public representatives provided a review of two versions of the Plain English Summary. Again, the views of the general public about breech birth research are likely to be different to those held by women who have experienced a term breech pregnancy themselves. One RDS reviewer expressed concern that if physiological breech birth were deemed ‘safe,’ women would feel pressured to choose a vaginal birth rather than a CS, and this would undermine the priority of ensuring women are well supported regardless of their choice of mode of birth.

Thank you

… to everyone who took the time to respond to my research proposal, to members of South London MVP for giving me permission to share their feedback and to Alison Bish for co-ordinating responses from RDS London. I am extremely grateful and confident the design is better for everyone’s involvement.

If you would like to view the tool I used for the Maternity Voices Partnership Meeting, you can download it here.