How safe is it to plan a vaginal breech birth with OptiBreech collaborative care?: analysis of cumulative data within the OptiBreech Multiple Trials Cohort

breech presentation, physiological breech birth, breech specialist midwives, OptiBreech, interim analysis, cohort study, multi-trial cohort ALL Metrics - Views Downloads How to cite this article Walker S, Das S, Stringer K et al. How safe is it to plan a vaginal breech birth with OptiBreech collaborative care?: analysis of cumulative data within the OptiBreech Multiple Trials Cohort [version 2; peer review: 2 approved, 1 approved with reservations]. NIHR Open Res 2025, 3:61 (https://doi.org/10.3310/nihropenres.13500.2) NOTE: If applicable, it is important to ensure the information in square brackets after the title is included in all citations of this article. Export Citation Sciwheel EndNote Ref. Manager Bibtex ProCite Sente Select a format first ▬ ✚ Research Article Revised How safe is it to plan a vaginal breech birth with OptiBreech collaborative care?: analysis of cumulative data within the OptiBreech Multiple Trials Cohort [version 2; peer review: 2 approved, 1 approved with reservations] Shawn Walker1-3, Sabrina Das2,3, Kate Stringer4, [...] Emma Spillane https://orcid.org/0000-0002-6663-7093 5, Amy Meadowcroft https://orcid.org/0000-0002-5934-0136 6, Siân Davies1, Jacana Bresson1, Alice Hodder1, Jasmine Kang1, The OptiBreech CollaborativeShawn Walker1-3, Sabrina Das2,3, [...] Kate Stringer4, Emma Spillane https://orcid.org/0000-0002-6663-7093 5, Amy Meadowcroft https://orcid.org/0000-0002-5934-0136 6, Siân Davies1, Jacana Bresson1, Alice Hodder1, Jasmine Kang1, The OptiBreech Collaborative PUBLISHED 14 Nov 2025 Author details Author details 1 King's College London, London, England, UK 2 Imperial College Health Partners, London, England, UK 3 Imperial College London, London, England, UK 4 Surrey and Sussex Healthcare NHS Trust, Redhill, England, UK 5 Kingston Hospital NHS Foundation Trust, London, England, UK 6 Northern Care Alliance NHS Foundation Trust, Salford, England, UK 2 Imperial College Health Partners, London, England, UK 3 Imperial College London, London, England, UK 4 Surrey and Sussex Healthcare NHS Trust, Redhill, England, UK 5 Kingston Hospital NHS Foundation Trust, London, England, UK 6 Northern Care Alliance NHS Foundation Trust, Salford, England, UK Shawn Walker Roles: Conceptualization, Data Curation, Formal Analysis, Funding Acquisition, Investigation, Methodology, Project Administration, Writing – Original Draft Preparation Roles: Conceptualization, Data Curation, Formal Analysis, Funding Acquisition, Investigation, Methodology, Project Administration, Writing – Original Draft Preparation Sabrina Das Roles: Investigation, Writing – Review & Editing Roles: Investigation, Writing – Review & Editing Kate Stringer Roles: Investigation, Writing – Review & Editing Roles: Investigation, Writing – Review & Editing Emma Spillane Roles: Conceptualization, Investigation, Writing – Review & Editing Roles: Conceptualization, Investigation, Writing – Review & Editing Amy Meadowcroft Roles: Investigation, Writing – Review & Editing Roles: Investigation, Writing – Review & Editing Siân Davies Roles: Data Curation, Validation, Writing – Review & Editing Roles: Data Curation, Validation, Writing – Review & Editing Jacana Bresson Roles: Data Curation, Project Administration, Validation, Writing – Review & Editing Roles: Data Curation, Project Administration, Validation, Writing – Review & Editing Alice Hodder Roles: Formal Analysis, Validation Roles: Formal Analysis, Validation Jasmine Kang Roles: Formal Analysis, Validation Roles: Formal Analysis, Validation OPEN PEER REVIEW REVIEWER STATUS OptiBreech collaborative care is a multi-disciplinary care pathway for breech presentation at term. The OptiBreech Multiple Trial Cohort is designed to host multiple trials related to care for breech presentation. This design enables prospective data collection for a large cohort of women planning a vaginal breech birth (VBB), to assess rare safety outcomes, while answering questions requiring a smaller, randomised sample nested within this cohort. OptiBreech database currently contains participants recruited from January 2022 to January 2024, including 67 women randomised to either OptiBreech care or standard care, and 147 women who received OptiBreech care and were not randomised. Primary outcomes included vaginal birth rate, composite neonatal morbidity and mortality and composite maternal neonatal morbidity and mortality. Descriptive statistics for the entire cohort were analysed in SPSS Version 29. Sub-group analyses were identified through participant involvement and engagement work as important to support informed decision-making. Of 117 women who planned a VBB at any point, 54 (46.2%) achieved a vaginal birth, compared to 36/96 (37.5%) of women who did not plan a VBB. Admission rates to a neonatal unit were similar, 5/117 (4.3%) versus 4/96 (4.2%). In this cohort, there was no severe neonatal morbidity following planned VBB, compared to 3/96 (3.1%) among the cohort who did not plan a vaginal breech birth and 2/61 (3.3%) among women who planned a cephalic birth after spontaneous or external cephalic version. Severe maternal morbidity following planned VBB was 12/115 (10.4%), compared to 9/95 (9.5%) for women who did not plan a VBB and 9/61 (14.8%) for women who planned a cephalic birth. Planning a VBB with OptiBreech collaborative care has thus far been as safe as not planning a VBB. Detecting differences in rare outcomes will require thousands of births. This report includes all outcomes reported during OptiBreech feasibility work. Further research will depend on future substantive funding. Around 1 in 20 pregnant women / birthing people experience a breech presentation (where baby is bottom-first instead of head-down in the womb) after 35 weeks of pregnancy. Women with a breech baby can choose to birth vaginally or by caesarean. Both breech babies and their mothers are at a higher risk of poor outcomes regardless of their type of birth, compared to pregnancies where babies have not been breech. It can also be difficult for clinicians to gain experience, hence limiting options and increasing risks for unexpected breech births. OptiBreech collaborative care is a new care model that aims to improve safety and care to offer women real choice. The need for this research, how it was designed, and how the on-going results are interpreted has been informed by women who use NHS services. It will require thousands of births, and take a long time, to determine if OptiBreech care reduces the number of babies who are seriously ill or die around the time of birth. This is already a low number, but we hope to reduce it further. We will also consider how women are able to give birth and their health after birth. It is important to women and clinicians that we share results of all births within our database regularly, so that they can make an informed decision about whether they would like to participate in OptiBreech research. Sponsors, funders, and ethics committees that oversee our research would like this information to make decisions about whether the research should continue. This research will eventually help policy makers decide if OptiBreech care should be implemented as standard within all NHS services. We will work with our patient and public involvement group to share findings through health professional training, conferences, reports to funders, stakeholder events, and social media. breech presentation, physiological breech birth, breech specialist midwives, OptiBreech, interim analysis, cohort study, multi-trial cohort Corresponding Author(s) Shawn Walker ([email protected]) Grant information: This project is funded by the National Institute for Health and Care Research (NIHR) (Grant number: NIHR300582). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Copyright: © 2025 Walker S et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. How to cite: Walker S, Das S, Stringer K et al. How safe is it to plan a vaginal breech birth with OptiBreech collaborative care?: analysis of cumulative data within the OptiBreech Multiple Trials Cohort [version 2; peer review: 2 approved, 1 approved with reservations]. NIHR Open Res 2025, 3:61 (https://doi.org/10.3310/nihropenres.13500.2) First published: 23 Nov 2023, 3:61 (https://doi.org/10.3310/nihropenres.13500.1) Latest published: 14 Nov 2025, 3:61 (https://doi.org/10.3310/nihropenres.13500.2) The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Data have been updated with final data from the OptiBreech cohort database. Minor revisions for clarity have been made, as recommended by reviewers. These include definitions for key terms used in tables. Before each table, key findings are summarised in text. This adds clarity, context and focus to the findings. Three new tables are added. These report infant feeding outcomes, by cohort and planned mode of birth, and outcomes following different types of cord management immediately following birth. In the discussion, a paragraph is added regarding the influence of PPIE work on the analyses that were undertaken and their presentation in the report. Data have been updated with final data from the OptiBreech cohort database. Minor revisions for clarity have been made, as recommended by reviewers. These include definitions for key terms used in tables. Before each table, key findings are summarised in text. This adds clarity, context and focus to the findings. Three new tables are added. These report infant feeding outcomes, by cohort and planned mode of birth, and outcomes following different types of cord management immediately following birth. In the discussion, a paragraph is added regarding the influence of PPIE work on the analyses that were undertaken and their presentation in the report. See the authors' detailed response to the review by Jennifer Barrowclough See the authors' detailed response to the review by Sara Morris See the authors' detailed response to the review by Robyn Schafer OptiBreech collaborative care is a specialist, multi-disciplinary care pathway for women and birthing people with a breech-presenting fetus at term, developed out of previous research and in collaboration with service users and clinicians1–4. Approximately 1 in 20 pregnant women have a breech presenting fetus at the end of pregnancy. Babies are at higher risk of poor outcomes, regardless of the mode of birth5. Mothers experience increased rates of surgical delivery and birth trauma. Balancing these risks through person-centred care, centred on the person’s values and life context, is improved when obstetricians and midwives have skill and experience in vaginal breech birth (VBB). Providers cannot offer the choice of a VBB if they do not have the skills to do so safely. Due to the way care is usually delivered in standard services, experience in VBB is difficult to acquire. Variations in skill and experience are dangerous and expensive. In 2021–22, the National Health Services’ (NHS) financial liabilities for claims of obstetric negligence causing cerebral palsy was £36.8 billion6. Twelve percent of obstetrics claims for cerebral palsy relate to poorly managed VBBs, despite representing only 0.3% of total births7. Our team developed an evidence-based management algorithm that aims to reduce the leading cause of breech birth-related injury: asphyxia8–10. Current NHS strategies to reduce risk focus on reducing the numbers of VBBs, through external cephalic version (ECV, turning the baby head-down) and/or planned caesarean birth (CB)11. An unintended effect has been a decline in health care professionals’ VBB skills12. This strategy has reduced the VBBs we can anticipate, resulting in a lack of learning opportunities for staff to safely manage those we cannot predict. Due to maternal choice, lack of universal diagnosis by ultrasound scan13, and late-changing fetal positions (unstable lie), VBBs continue to occur, but their rarity makes them vulnerable. OptiBreech collaborative care is an alternative strategy that differs from UK NHS standard care in the following ways: The service is co-ordinated by a Breech Specialist Midwife1,4 with support from a Breech Lead Obstetrician. Women who prefer to plan a VBB are actively supported, and staff maximise the learning opportunity from each planned VBB. The multidisciplinary team prepares for these births and manages them according to the OptiBreech guideline and algorithm. Professionals with advanced training in physiological breech birth14,15 attend VBBs whenever possible. A small, experienced team provides continuity for women and professionals2; their role is to train and support the wider team. This practice includes the option of upright maternal birthing positions4,16. Within the OptiBreech collaborative care pathway, women are offered all guideline-recommended options: VBB, ECV, and planned CB. Women find this service beneficial, regardless of their mode of birth1. Due to substantial differences in clinical practices and the way services are delivered, OptiBreech care is expected to result in different safety outcomes from standard care. The current logic model and TIDieR checklist17 for OptiBreech collaborative care have been reported in previous publications1,18. The OptiBreech training package has been described in detail in evaluation publications14,15. The OptiBreech Clinical Practice Guideline is included in the protocol uploaded to the ISRCTN registration19. Much of this information is also available on the project’s engagement website, optibreech.uk. Patient and Public Involvement and Engagement (PPIE) work aimed to ensure the study’s design, analysis, reporting, and interpretation were influenced by women who have lived experience of planning or attempting to plan a VBB. Previous research indicated this population was least well served within current NHS standard care, and this work aimed to improve their outcomes and experience of care1,20–22, while maintaining choice and good outcomes for all women using the service. This paper reports all data collected during the OptiBreech feasibility trial, which closed to enrolment on 31 January 2024. The purpose of reporting this analysis is to provide women and clinicians with as much up-to-date information as possible about what they can expect when planning a VBB with OptiBreech care, for those services continuing to operate, and to inform future research. We have chosen this publication venue (NIHR Open Research) to enable transparent reporting and updating as the cohort grows, so that all stakeholders have contemporaneous information on which to base decisions. Throughout the paper, we focus on sex-specific terminology ‘women’ and ‘mothers’ for clarity, and because all participants self-reported their gender identity as ‘female.’ We also acknowledge that some birthing people do not identify with the sex they were assigned at birth and should receive care that respects their identity. The OptiBreech Multiple Trial Cohort was designed to host multiple trials related to care for breech presentation in the third trimester and birth. This is to enable prospective data collection for a large cohort of women planning a VBB with OptiBreech collaborative care, to assess rare safety outcomes, while answering questions requiring a smaller, randomised sample that could be nested within this cohort. Stakeholder involvement was facilitated through multiple public meetings, held in person and on-line during the research design stage23. Two lay members of the Trial Steering Committee and one member of the research team were service users with lived experience of planning a VBB. Additional service users with lived experience of planning a VBB participated as members of the research team during qualitative work to refine the OptiBreech care pathway intervention1,22 and consensus work to identify and prioritise outcome measures24,25. PPIE input especially influenced the way we analysed and presented our results. Our PPIE group prioritised knowing how outcomes for VBBs compared with those for planned and actual cephalic births, regarded as the ‘normal’ care pathway. One of the challenges in breech research is the constantly moving parts – fetal presentation can change up to the point of labour and sometimes during; women may initially prefer one plan but change their minds for various reasons other than clinical concerns; and for each planned mode of birth, a portion of women will have a different mode of birth than the one they chose, due to the unpredictable nature of labour and birth. For this reason, we have performed several subgroup analyses that interrogate the data from different points of view. For each section, we begin with the question that the analysis answers, from the point of view of policy makers and/or service leaders, and from the point of view of women and birthing people making informed decisions about their care options. Service users also advocated for an equity analysis due to growing awareness of increased risk of adverse outcomes among women of minoritised ethnicity and skin colour in the UK26. Demographic information has been reported in line with the latest NICE style guide27. Inclusion criteria for the OptiBreech cohort are: Live, singleton pregnancy with a breech-presenting fetus confirmed by ultrasound scan; Over 16 years of age; Referred for specialist care for breech presentation antenatally from 32 weeks; Breech presentation from 37 weeks discovered in labour; Requesting or preferring a vaginal birth; and Giving informed consent to participate to contribute data to the cohort study. Exclusion criteria for the cohort are: Studies currently included in the OptiBreech database are listed below and summarised in Figure 1: Participant Flow 1) The OptiBreech Care Trial: a feasibility study for a pragmatic trial of care for women with a breech-presenting baby at term. Randomised participants (68) were recruited between 10 January 2022 and 09 June 2022. Inclusion and exclusion criteria were more narrowly defined and are reported in detail in the pilot trial report28. Cohort participants were recruited until 31 January 2024 and focused on women who preferred to plan a VBB regardless of whether their baby remained in a breech position. This study was funded by the UK National Institute for Health and Care Research (NIHR, 300582) and sponsored by King’s College London. Ethics approval was obtained from the West London & GTAC Research Ethics Committee (21/LO/0808, 19 November 2021). The pilot trial was prospectively registered with the ISRCTN (14521381, 18 October 2021)19. The full protocol is available on the trial registration page19. Participants were recruited following a referral for counselling and/or care relating to breech presentation in the third trimester. The consent and randomisation process for the OptiBreech Care feasibility pilot has been described elsewhere28. Information sources about the OptiBreech Care pathway, including all Participant Information Sheets and Consent Forms, was available via the OptiBreech engagement website (optibreech.uk) and wherever possible provided to women in advance of their appointment. Participants randomised to or requesting OptiBreech care received collaborative care co-ordinated and led by a specialist midwife. They were informed that this was a new care pathway and that they could request standard obstetric care if they preferred. Each participant provided consent to participate via written or e-consent form. Demographic data on ethnicity and gender was self-reported at the same time. Following the end of the pilot trial, recruitment focused on women requesting OptiBreech care due to a preference for vaginal birth, regardless of whether their baby remained in a breech position. Participants were able to withdraw consent at any time if they wished. Where consent was withdrawn, this is indicated in the Participant Flow (Figure 1), but no data has been reported. Participants in the ‘standard care’ arm have received care that does not involve access to OptiBreech-trained specialists for antenatal care or birth. Generally, they were offered ECV as a first-line intervention and/or referred to their named obstetric consultant’s antenatal clinic for further counselling regarding mode of birth if ECV failed or was declined. Participants in the OptiBreech care arm were counselled by a member of the OptiBreech team and were offered the option of planning a VBB with OptiBreech support, attempting an ECV, or planning a pre-labour CB from 39 weeks gestation. This report (v2.0) includes the cohort’s demographics and short-term outcomes, including: mode of birth, safety, infant feeding and fidelity outcomes, measured at discharge from birth care. Below each Table (1–16), a key is included that defines medical terms and abbreviations and provides information on how and when the outcomes included in that table were measured. Descriptive statistics only are reported. The study was not designed or powered to enable any inferential statistics. However, one aim of reporting the descriptive data in this way is to enable the design of future, appropriately powered investigations, based on the descriptive incidence rates. This report is an analysis of a compete feasibility study data set. We deal with missing data by reporting the current denominator of available data, for each outcome, where this is not equivalent to the total number of cases. During each interim analysis process, the team cleans the data by identifying missing data points and following up with site PIs, to ensure they are available for future cohort analyses. An interim analysis was initially done by one member of the team (SW or SMD) using SPSS Version 29.0.1.0. Table data were checked against output files by other members of the team (SW, SMD, or JB). To verify the analysis, JK and AH repeated a sub-section of the analysis by randomisation arm / cohort using Stata/MP version 17.0. Analysis of the final data set was completed and checked by the lead author (SW0 Baseline demographics are analysed by cohort (randomisation arm, non-randomised cohort, and overall OptiBreech care cohort). Presentation on admission, mode of birth and safety outcomes were assessed by: 1) cohort; 2) plan following first counselling (intention to treat); 3) those who planned a VBB at any point versus those who had not and those who had planned a cephalic birth; 4) actual VBBs versus vaginal cephalic births; 5) presentation on admission for labour/birth care; and 6) ethnicity. The group ‘did not plan a VBB at any point’ includes women who planned a caesarean birth and women who planned a cephalic birth, including those whose fetus was discovered to be presenting breech in labour. ‘Planned cephalic births’ included all those whose breech presentations were identified in the third trimester whose baby turned spontaneously or via ECV following recruitment, and those whose fetus was discovered to be presenting breech in labour but had planned a cephalic birth. These subgroup analyses were chosen because 1) this comparison enables comparison of the non-randomised cohort with the randomised cohorts; 2) PPIE group members valued this analysis to support informed decision-making; 3) these are the comparisons most often used in large observational cohort studies; 4) this comparison was prioritised by PPIE group members; 5) cephalic presentation at birth is evaluated as an outcome in Cochrane Reviews concerning the management of breech presentation at term; and 6) our PPI group was keen to ensure non-white-British and Black or Brown participants could access and were not disadvantaged within this model of care. Infant feeding outcomes are analysed by cohort (standard care vs OptiBreech care) and whether the women had planned a VBB or cephalic birth. Fidelity measures are reported for actual VBBs only, analysed according to whether there was a professional present who had completed the OptiBreech training, versus whether there was no OptiBreech trained professional present. SW and this research are funded by a National Institute for Health and Care Research (NIHR) Advanced Fellowship. The NIHR had no role in study design, data collection, data analysis, data interpretation, or writing of the report. Breech Birth Network, a not-for-profit Community Interest Company, provided training for OptiBreech teams, educational resources, and funding for PPIE, and conference presentations.

are presented by sub-group analysis category. With each table, we include the key questions the analysis seeks to answer, by stakeholder group. In all instances, it is not yet possible to detect any significant differences between groups, due to the small sample size. Table 1 Key Questions: 1) How do characteristics of participants differ between ‘standard care’ and ‘OptiBreech care’ groups? 2) Are people from minoritized groups able to access participation in this research? Gestational age at enrolment was similar for women randomised in the pilot trial, but on average two weeks later for women recruited to the observational study. This is influenced by the high number of women in the cohort transferring care from another booking hospital to access participation in this research (25/147, 17.0%). All randomised and most non-randomised (90.5%) participants were recruited prior to the start of labour. Over half of participants were from UK minority (non-white-British) backgrounds, and 26.5% (48/181) were Black or Brown women. Table 2 Key Questions: 1) Service leaders: How does the model of care influence the vaginal birth rate? 2) Service users: How likely am I to achieve the vaginal birth I want within OptiBreech care? The highest percentage of vaginal birth were seen among women recruited to the OptiBreech Care observational cohort (71/146, 48.6%), compared to women randomised to either standard care (8/33, 24.2%) or OptiBreech Care (11/34, 32.4%). Women randomised to standard care had a higher percentage of in-labour caesarean birth (12/33, 35.4%), compared to women randomised to OptiBreech Care (7/34, 20.6%) or recruited to the cohort (40/146, 27.4%). Table 3 Key Questions: 1) Service leaders: How does the model of care influence neonatal outcomes? 2) Service users: How likely am I to be separated from my baby following birth? How likely is my baby to be unwell? Neonatal outcomes were similar across all models of care. When women received OptiBreech care, babies were more likely to be admitted to transitional care (21/180, 11.7%), compared to standard care (2/33, 6.1%). When women received OptiBreech care, babies were less likely to be admitted to a neonatal unit (8/180, 3.9%), compared to standard care (2/33, 6.1%). Table 4 Key Questions: 1) Service leaders: How does the model of care influence maternal outcomes? 2) Service users: How likely am I to be unwell after my birth? What are the outcomes for my perineum likely to be? Admissions to maternal HDU were similar across groups. Women receiving OptiBreech Care were less likely to experience severe morbidity prior to discharge (randomised: 4/34, 11.8%; non-randomised: 12/144, 8.3%), compared to standard care (5/32, 15.6%). There were no maternal deaths. Women receiving OptiBreech Care had lower rates of intact perineum (126/179, 70.4%), compared to standard care (29/33, 87.9%), reflecting the increased vaginal birth rate. Analysis by first plan following counselling (entire cohort) Table 5 Key Questions: 1) Service leaders: How does an ECV service affect the vaginal birth rate? 2) Service users: How likely am I to have the type of birth I choose to plan? In this study, women who planned a VBB without an initial attempt at ECV had a higher vaginal birth rate (29/58, 50%) than those women who planned an attempt at ECV (55/135, 40.7%, includes successful and unsuccessful attempts). When women planned a pre-labour caesarean birth, 12.5% (2/16) had a VBB despite this plan. Table 6 Key Questions: 1) Service leaders: How does an ECV service affect neonatal outcomes? 2) Service users: How will my care choices influence outcomes for my baby? In this cohort, women who planned a VBB had better neonatal outcomes than women who planned an ECV or had breech presentation diagnosed for the first time in labour. The exception was Apgar score of <7 and 5 minutes, which only occurred among the cohort of women who planned a VBB (2/58, 3.4%). Table 7 Key Questions: 1) Service leaders: How does an ECV service affect maternal outcomes? 2) Service users: How will my care choices influence my health after birth? Women who planned a VBB had lower rates of severe maternal morbidity (5/56, 8.9%), compared to women who planned an ECV (14/134, 10.4%) or planned a pre-labour caesarean birth (2/16 (12.5%). Table 8 Key Questions: 1) Service leaders: How does achieving cephalic presentation at birth affect vaginal birth rates? 2) Service users: How likely am I to have the type of birth I choose to plan? How will my baby’s position at the time of birth influence this? In this cohort, women who planned a VBB at any point had fewer overall vaginal births (54/117, 46.2%) than women who planned a cephalic birth (37/61, 60.7%) after the baby turned, spontaneously or by ECV. Women who planned a VBB had fewer in-labour caesarean births (32/117, 27.4%) than women who planned a cephalic birth (20/61, 32.8%). Women who gave birth vaginally to a baby in breech position had fewer instrumental deliveries (3/56, 5.4%) than women who gave birth to a head-down baby (4/34, 11.8%). Women whose baby was in a breech position when admitted for labour or birth had lower rates of vaginal birth (53/153, 39.2%) than women whose baby was in a cephalic position (35/57, 61.4%). Table 9 Key Questions: 1) Service leaders: How does achieving cephalic presentation at birth affect neonatal outcomes? 2) Service users: How will my care choices influence outcomes for my baby? In this cohort, the babies of women who planned a VBB at any point received any form of neonatal resuscitation (22/117, 18.8%) more often than when women planned a cephalic birth (6/61, 9.8%) after the baby turned, spontaneously or by ECV. The babies of women who planned a VBB had less severe neonatal morbidity (0/117) than women who planned a cephalic birth (2/61, 3.3%). The babies of women who planned a VBB were admitted to transitional care less (11/117, 9.4%) than women who planned a cephalic birth (10/61, 16.1%). These results were similar for babies born vaginally in a breech position, compared to cephalic births, and for babies admitted for labour/birth in a breech position, compared to a cephalic position. Admissions to a neonatal unit were similar across groups, and there were no neonatal deaths. Table 10 Key Questions: 1) Service leaders: How does achieving cephalic presentation at birth affect maternal outcomes? 2) Service users: How will my care choices influence my health after birth? Women who planned a VBB at any point were admitted to a maternal HDU less often (4/117, 3.4%) than women who planned a cephalic birth (4/61, 6.6%), after the baby turned spontaneously or by ECV. Women who planned a VBB at any point experienced less severe morbidity (12/115, 10.3%) than women who planned a cephalic birth (9/61, 14.8%). Women whose babies were in a breech position on admission for labour/birth experienced less severe morbidity (12/150, 8.0%) than women whose babies were in a cephalic position (8/57, 14.0%). Serious maternal morbidity was higher for women who gave birth vaginally to a breech baby (6/56, 10.7%), compared to vaginal birth of a cephalic baby (3/34, 8.8%). Table 11 Key Questions: 1) Service leaders: How do vaginal birth rates compare between ethnic groups in this cohort? 2) Service users: How do vaginal birth rates compare between ethnic groups? Rates of vaginal birth were similar across ethic groups. Black or Brown participants had VBBs more often (20/55, 36.4%) than white participants (36/158, 22.8%). White women experienced higher rates of caesarean birth at full dilation (white British: 7/101, 6.9%; all white participants: 7/158, 4.4%) than other ethnic groups (non-white British: 1/112, 0.9%; Black or Brown participants: 1/55, 1.8%). Table 12 Key Questions: 1) Service leaders: How does ethnicity influence neonatal outcomes within an OptiBreech care model? 2) Service users: How will my ethnicity affect outcomes for my baby within an OptiBreech care model? The babies of white women experienced more severe neonatal morbidity (white British: 3/101, 3.0%; all white participants: 2/158, 1.3%) than other ethnic groups (non-white British: 0; Black or Brown participants: 0). Table 13 Key Questions: 1) Service leaders: How does ethnicity influence maternal outcomes within an OptiBreech care model? 2) Service users: How will my ethnicity affect my health after birth within an OptiBreech care model? White women were admitted to a maternal HDU less often (white British: 3/101, 3.0%; all white participants: 7/158, 4.4%) than other ethnic groups (non-white British: 8/112, 7.1%; Black or Brown participants: 4/55, 7.3%). White women experienced lower overall rates of severe maternal morbidity (white British: 9/99, 9.1%; all white participants: 14/156, 9.0%) than other ethnic groups (non-white British: 12/112, 20.8%; Black or Brown participants: 7/54, 13.0%). When women gave birth vaginally, white women experienced higher rates of episiotomy (white British: 14/46, 30.4%; all white participants: 19/63, 30.2%) than other ethnic groups (non-white British: 8/44, 18.2%; Black or Brown participants: 3/27, 11.1%). Minority ethnic groups experienced higher rates of OASI (non-white British: 2/44, 4.5%; Black or Brown participants: 2/27, 7.4%) than white women (white British: 0 all white participants: 0). Table 14 Key Questions: 1) Service leaders: How does provision of OptiBreech collaborative care influence women’s ability to breastfeed when they have chosen this? 2) Service users: How will OptiBreech care influence my ability to feed my baby the way I have chosen? Breastfeeding outcomes were similar, whether women received standard care, compared OptiBreech care, and whether they planned a VBB at any point, compared to a cephalic birth. Table 15 Key Questions: 1) Service leaders: How does the presence of an OptiBreech team member affect adherence to the OptiBreech Algorithm? 2) Service users: How does the presence of an OptiBreech team member affect my ability to give birth in an upright position if I want to? How does the presence of an OptiBreech team member affect the likelihood that my baby’s umbilical cord will remain intact until after s/he has started breathing? Most VBBs in this cohort were attended by a midwife (39/49, 79.6%), compared to an obstetrician (10/49, 20.4%). When births were attended by an OptiBreech team member, the attendant was more likely to have attended >10 VBBs (17/48, 35.4%) or >20 VBBs (21/48, 43.8%), compared to when no OptiBreech trained professional was present (0/6). When an OptiBreech-trained professional was present, women gave birth in an upright position 77.6% (38/49) of the time. When an Opti-Breech-trained professional was present, adherence to the Physiological Breech Birth Algorithm was >90% with regards to timings (<5 minutes pelvis-to-birth; <7 minutes rumping-to-birth). However, for only 61.2% (30/49) of babies did the umbilicus remain intact until after the onset of respirations. Table 16 Key Questions: 1) Service leaders: How does maintaining the umbilicus intact until after the onset of respirations impact neonatal outcomes? 2) Service users: Will keeping the umbilicus intact until after my baby has started breathing affect whether we need to be separated due to admission to the neonatal unit? When the umbilicus remained intact until after the onset of respirations, in adherence to OptiBreech guidance, compared to when it was immediately clamped and cut: fewer babies had an Apgar under 7 at 5 minutes (0/145 vs 2/64, 3.1%), fewer babies were admitted to transitional care (11/145, 7.6% vs 11/64, 17.2%), and fewer babies were admitted to a neonatal unit (4/145, 2.8% vs 4/64, 6.3%). These differences were more pronounced for the subgroup of neonates who had an Apgar less than 7 at 1 minute. Data from the OptiBreech Care feasibility and pilot trial indicate that providing support for planned VBB within an OptiBreech collaborative care pathway has been as safe as a planned cephalic birth in the same hospitals. While this is the largest data set of planned vaginal breech births published in the UK since 200529, the sample size is still too small to evaluate rare but important outcomes, such as severe neonatal morbidity or mortality. The Royal College of Obstetricians and Gynaecologists (RCOG) guideline estimates that perinatal mortality following planned caesarean birth at 39 weeks is 0.5/1000, following planned cephalic birth is 1/1000, and following planned vaginal breech birth is 2/10005. Evaluating OptiBreech care for this outcome will require thousands of births. Our intention with the multiple trials cohort is to facilitate multiple nested randomised controlled trials to answer important questions about breech care with different endpoints, while accumulating a sufficient sample to evaluate rare outcomes such as perinatal mortality. This will refine the OptiBreech care pathway for maximum efficiency and effectiveness, for all women requiring breech care. Prior to the start of this cohort, two preliminary studies were done. The first evaluated the OptiBreech training package (‘Physiological Breech Birth’) within NHS settings15. This observed a serious neonatal morbidity rate of 0/21 (same composite, 0%) among births attended by an OptiBreech trained attendant, compared to 5/69 (7.2%) among births where the attendant had NOT attended the training15. This suggests the results of the Term Breech Trial are still relevant to standard care within the UK30. The second evaluated the feasibility of implementing OptiBreech collaborative team care for planned VBBs18. In this study, among 82 planned VBBs, one serious adverse outcome (same composite, 1.2%) occurred. In the OptiBreech cohort reported in this paper, 117 women have planned a VBB, with no serious adverse neonatal outcomes. We have therefore reported 220 prospective VBBs across three studies, including the present study, with one serious adverse neonatal outcome (0.45%). This is very near to the rate of adverse outcomes observed among low-risk women planning cephalic (head-first) births in the UK-based Birthplace in England study (0.43%)31. Neonatal admission rates across the feasibility studies following planned VBBs have been below 5%, similar to rates for all term births in the UK32. We feel our results so far are due to strong qualitative work to develop the programme theory for the OptiBreech collaborative care model. Our logic model was developed and refined through: frequent and meaningful PPIE activities; systematic reviews to establish background, questions and women’s experiences8,22,33; Delphi consensus methods, including clinicians and service users, on core competencies and important outcomes4,16,24,25,34; grounded theory methods to describe how clinicians learn breech skills2,3; qualitative interviews with women1 and staff; implementation feasibility work to prepare for a substantive clinical trial1,18; and a pilot randomised trial28. Detailed observational work also theoretically underpins our practice guidelines, including video analysis and case control studies to define ranges of ‘normal’ in breech births8–10. The OptiBreech Algorithm aims to reduce the leading cause of breech birth-related injury: asphyxia8–10. Our team has raised concerns previously that current guidelines are not optimally safe10,35. Historically, breech practice has not been based on evidence, particularly around the expected time intervals as the breech baby emerges8. This is the fourth paper in which we report that, in most cases with good outcomes, the birth has completed within three to five minutes of the birth of the fetal pelvis9,10,18. We strongly feel this should be regarded as ‘normal for breech.’ Our OptiBreech guideline continues to recommend attendants aim for the birth to be complete within five minutes from the birth of the pelvis, including time for manoeuvres. It is especially important for novices, who are inherently less confident to intervene, to have clear guidelines that alert them when a threshold of increased risk is approaching. Current RCOG5 and PROMPT36 guidelines recommend assisting only after five minutes have passed following birth of the pelvis and emphasise a ‘hands off’ approach. Our guideline promotes using maternal effort and movement (‘wiggle and push’) as a first-line intervention if advancement pauses for 30 seconds or more at any point after the birth of the pelvis. This optimises maternal agency and minimises the need for attendants to manually intervene. We feel waiting five minutes to assist the birth offers no advantages. Rather, it increases the risk of an adverse outcome should the attendant discover after five minutes that the delay is due to arm or head entrapment, which takes further time to resolve. There are limitations to presenting feasibility data in this way. We cannot assume that the results will continue in the same manner, and a much larger sample size will be needed to determine overall safety. Although local investigators have an obligation to report serious adverse outcomes, currently missing data may reveal in future analyses outcomes that are less positive than they currently appear. These results also do not apply to all planned VBBs. The OptiBreech teams follow a specific care algorithm10 with manoeuvres specific to upright breech birth37, the presence of an OptiBreech team member increases the likelihood that this will be followed2,18, and their presence facilitates shared learning from each birth throughout the team. Outside of this model of care, the absence of one or more of these potential mechanisms may impact outcomes. This analysis has also helped us to identify areas that require further support for clinical change. Our guideline also recommends that, should the baby be born in poor condition, resuscitation be initiated with the umbilical cord intact16. Current evidence supports leaving the umbilical cord intact until after the onset of respirations38,39, and service users have identified this in PPIE work as an important and under-studied outcome for them25,40. However, these data indicate OptiBreech teams are not optimally achieving this. Understanding why and developing a strategy for addressing this difficult area of implementation will require further research and collaboration with neonatal teams. While most research has focused on premature babies41, for whom this practice provides significant benefit, the difference in neonatal admission rates in our data suggest it may be beneficial for term babies as well. We remind readers that this is a feasibiity data set. Some data points are missing, and in a small data set, results can change dramatically in a short period. However, at this point, we are encouraged by this very positive set of pilot data, which will grow with each trial funded. Figshare: OptiBreech Care IRAS 303028 Data Sets, https://doi.org/10.6084/m9.figshare.c.6386370.v342. This project contains the following underlying data: OptiBreech Care IRAS 303028 feasibility data to 21 October 2024 OptiBreech Care IRAS 303028 cohort interim data to 8 September 2023 OptiBreech Codebook data to 8 September 2023 STROBE and GRIPP2 checklists for analysis of OptiBreech Care data to 8 September 2023 Data are available under the terms of the Creative Commons Attribution 4.0 International license (CC-BY 4.0). We are grateful to the women who have participated in this research and the healthcare professionals who have delivered it, amidst the challenging circumstances of a pandemic and multiple staff strikes. The OptiBreech Collaborative contributing to the observational cohort include: Helen Le Grys and Eleanora Palena (Royal Cornwall Hospital, Principal Investigator and Lead Midwife), Louisa Davidson and Lucy Williamson (Birmingham Women’s Hospital, Principal Investigator and Lead Midwife), Lenka Magurova and Danielle Nixon (Lewisham and Greenwich NHS Trust, Principal Investigators), Gemma Botterill (Imperial College Healthcare NHS Trust, Consent and Data Collection), Zainab Sarwar (The Royal Oldham Hospital, Northern Care Alliance, Principal Investigator), Avni Batish (Surrey and Sussex Healthcare NHS Trust, East Surrey Hospital, Lead Obstetrician), Florence Wilcock (Kingston Hospital NHS Foundation Trust, Lead Obstetrician), Philippa Corson (The Royal London Hospital, Barts Health NHS Trust, Lead Obstetrician), and Priscilla Dike (The Royal London Hospital, Barts Health NHS Trust, Principal Investigator). Faculty Opinions recommendedReferences - 1. Dasgupta T, Hunter S, Reid S, et al.: Breech specialist midwives and clinics in the OptiBreech Trial feasibility study: an implementation process evaluation. Birth. 2023; 50(3): 596–605. PubMed Abstract | Publisher Full Text - 2. Walker S, Parker P, Scamell M: Expertise in physiological breech birth: a mixed-methods study. Birth. 2018; 45(2): 202–209. PubMed Abstract | Publisher Full Text - 3. Walker S, Scamell M, Parker P: Deliberate acquisition of competence in physiological breech birth: a grounded theory study. Women Birth. 2018; 31(3): e170–e177. PubMed Abstract | Publisher Full Text - 4. Walker S, Scamell M, Parker P: Standards for maternity care professionals attending planned upright breech births: a Delphi study. Midwifery. 2016; 34: 7–14. PubMed Abstract | Publisher Full Text - 5. Impey L, Murphy D, Griffiths M, et al.: Management of breech presentation: green-top guideline no. 20b. BJOG. 2017; 124(7): e151–e177. PubMed Abstract | Publisher Full Text - 6. NHS Resolution: NHS Resolution - Annual report and accounts 2021/22. Published online 2021; Accessed April 16, 2023. Reference Source - 7. Magro M: Five years of cerebral palsy claims: a thematic review of NHS Resolution data. Published 2017; Accessed August 24, 2019. Reference Source - 8. Bresson J, Christie K, Walker S: Not too fast, not too slow: a review of historical trends in vaginal breech time management. Eur J Obstet Gynecol Reprod Biol. 2023; 287: 216–220. PubMed Abstract | Publisher Full Text - 9. Reitter A, Halliday A, Walker S: Practical insight into upright breech birth from birth videos: a structured analysis. Birth. 2020; 47(2): 211–219. PubMed Abstract | Publisher Full Text | Free Full Text - 10. Spillane E, Walker S, McCourt C: Optimal time intervals for vaginal breech births: a case-control study [version 2; peer review: 1 approved, 2 approved with reservations, 1 not approved]. NIHR Open Res. 2022; 2: 45. PubMed Abstract | Publisher Full Text | Free Full Text - 11. Impey L, Murphy D, Griffiths M, et al.: External cephalic version and reducing the incidence of term breech presentation: green-top guideline no. 20a. BJOG. 2017; 124(7): e178–e192. PubMed Abstract | Publisher Full Text - 12. Post WM, Vlemmix F, de Hundt M, et al.: Does vaginal breech delivery have a future despite low volumes for training? Results of a questionnaire. Eur J Obstet Gynecol Reprod Biol. 2018; 229: 123–126. PubMed Abstract | Publisher Full Text - 13. Salim I, Staines-Urias E, Mathewlynn S, et al.: 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. PubMed Abstract | Publisher Full Text | Free Full Text - 14. Walker S, Reading C, Siverwood-Cope O, et al.: Physiological breech birth. Evaluation of a training programme for birth professionals. Pract Midwife. 2017; 20(2): 25–28. PubMed Abstract - 15. 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. PubMed Abstract | Publisher Full Text - 16. Walker S, Scamell M, Parker P: Principles of physiological breech birth practice: a Delphi study. Midwifery. 2016; 43: 1–6. PubMed Abstract | Publisher Full Text - 17. Hoffmann TC, Glasziou PP, Boutron I, et al.: Better reporting of interventions: Template for Intervention Description and Replication (TIDieR) checklist and guide. BMJ. 2014; 348(3): g1687. PubMed Abstract | Publisher Full Text - 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. Pilot Feasibility Stud. 2023; 9(1): 80. PubMed Abstract | Publisher Full Text | Free Full Text - 19. Walker S: ISRCTN14521381: The OptiBreech Care Trial: a small randomised trial to determine whether a large trial is possible for women with a breech-presenting baby at term. ISRCTN Registry. Published 2021; Accessed January 15, 2023. Publisher Full Text - 20. Staniszewska S, Brett J, Simera I, et al.: GRIPP2 reporting checklists: tools to improve reporting of Patient and Public Involvement in research. BMJ. 2017; 358: j3453. PubMed Abstract | Publisher Full Text | Free Full Text - 21. Morris SE, Sundin D, Geraghty S: Women’s experiences of breech birth decision making: an integrated review. Eur J Midwifery. 2022; 6: 2. PubMed Abstract | Publisher Full Text | Free Full Text - 22. Roy R, Gray C, Prempeh-Bonsu CA, et al.: What are women’s experiences of seeking to plan a vaginal breech birth? A systematic review and qualitative meta-synthesis [version 1; peer review: 2 approved]. NIHR Open Res. 2023; 3: 4. PubMed Abstract | Publisher Full Text | Free Full Text - 23. Walker S: PPI: influence on design – the OptiBreech Project. The OptiBreech Project Blog. Published 2019; Accessed September 14, 2022. Reference Source - 24. Walker S, Dasgupta T, Shennan A, et al.: Development of a core outcome set for effectiveness studies of breech birth at term (Breech-COS)—an international multi-stakeholder Delphi study: study protocol. Trials. 2022; 23(1): 249. PubMed Abstract | Publisher Full Text | Free Full Text - 25. Walker S, Dasgupta T, Halliday A, et al.: Development of a core outcome set for effectiveness studies of breech birth at term (Breech-COS): a systematic review on variations in outcome reporting. Eur J Obstet Gynecol Reprod Biol. 2021; 263: 117–126. PubMed Abstract | Publisher Full Text - 26. Jardine J, Walker K, Gurol-Urganci I, et al.: Adverse pregnancy outcomes attributable to socioeconomic and ethnic inequalities in England: a national cohort study. Lancet. 2021; 398(10314): 1905–1912. PubMed Abstract | Publisher Full Text - 27. National Institute for Health and Care Excellence: Talking about people [ECD1]. NICE style guide. Published February 20, 2023; Accessed March 28, 2023. Reference Source - 28. Walker S, Spillane E, Stringer K, et al.: OptiBreech collaborative care versus standard care for women with a breech-presenting fetus at term: a pilot parallel group randomised trial to evaluate the feasibility of a substantive trial nested within a cohort. ResearchGate Pre-Print. Published online 2023. Publisher Full Text - 29. Pradhan P, Mohajer M, Deshpande S: Outcome of term breech births: 10-year experience at a district general hospital. BJOG. 2005; 112(2): 218–222. PubMed Abstract | Publisher Full Text - 30. Hannah ME, Hannah WJ, Hewson SA, et al.: Planned caesarean section versus planned vaginal birth for breech presentation at term: a randomised multicentre trial. Term Breech Trial Collaborative Group. Lancet. 2000; 356(9239): 1375–1383. PubMed Abstract | Publisher Full Text - 31. Birthplace in England Collaborative Group, Brocklehurst P, Hardy P, et al.: Perinatal and maternal outcomes by planned place of birth for healthy women with low risk pregnancies: the Birthplace in England national prospective cohort study. BMJ. 2011; 343: d7400. PubMed Abstract | Publisher Full Text | Free Full Text - 32. Battersby C, Michaelides S, Upton M, et al.: Term admissions to neonatal units in England: a role for transitional care? A retrospective cohort study. BMJ Open. 2017; 7(5): e016050. PubMed Abstract | Publisher Full Text | Free Full Text - 33. Walker S, Breslin E, Scamell M, et al.: Effectiveness of vaginal breech birth training strategies: an integrative review of the literature. Birth. 2017; 44(2): 101–109. PubMed Abstract | Publisher Full Text - 34. Walker S, Perilakalathil P, Moore J, et al.: Standards for midwife practitioners of external cephalic version: a Delphi study. Midwifery. 2015; 31(5): e79–e86. PubMed Abstract | Publisher Full Text - 35. Walker S: No more ‘hands off the breech’. Pract Midwife. 2020; 23(6): 1–8. Accessed July 25, 2020. Publisher Full Text - 36. PROMPT Wales: Algorithm for the management of unplanned vaginal breech birth. Published online 2023. - 37. Walker S, Spillane E: Face-to-pubes rotational maneuver for bilateral nuchal arms in a vaginal breech birth, resolved in an upright maternal position: a case report. Birth. 2020; 47(2): 246–252. PubMed Abstract | Publisher Full Text - 38. Bhatt S, Polglase GR, Wallace EM, et al.: Ventilation before umbilical cord clamping improves the physiological transition at birth. Front Pediatr. 2014; 2: 113. PubMed Abstract | Publisher Full Text | Free Full Text - 39. Badurdeen S, Roberts C, Blank D, et al.: Haemodynamic instability and brain injury in neonates exposed to hypoxia–ischaemia. Brain Sci. 2019; 9(3): 49. PubMed Abstract | Publisher Full Text | Free Full Text - 40. Johnstone N: PPI: proposal development phase – implementation of bedside resuscitation. The OptiBreech Project Blog. Published 2023; Accessed March 16, 2023. Reference Source - 41. Katheria AC: Neonatal resuscitation with an intact cord: current and ongoing trials. Children (Basel). 2019; 6(4): 60. PubMed Abstract | Publisher Full Text | Free Full Text - 42. Walker S: OptiBreech Care IRAS 303028 Data Sets. figshare. Collection. 2025. http://www.doi.org/10.6084/m9.figshare.c.6386370.v3 Author details Author details 1 King's College London, London, England, UK 2 Imperial College Health Partners, London, England, UK 3 Imperial College London, London, England, UK 4 Surrey and Sussex Healthcare NHS Trust, Redhill, England, UK 5 Kingston Hospital NHS Foundation Trust, London, England, UK 6 Northern Care Alliance NHS Foundation Trust, Salford, England, UK 2 Imperial College Health Partners, London, England, UK 3 Imperial College London, London, England, UK 4 Surrey and Sussex Healthcare NHS Trust, Redhill, England, UK 5 Kingston Hospital NHS Foundation Trust, London, England, UK 6 Northern Care Alliance NHS Foundation Trust, Salford, England, UK Shawn Walker Roles: Conceptualization, Data Curation, Formal Analysis, Funding Acquisition, Investigation, Methodology, Project Administration, Writing – Original Draft Preparation Roles: Conceptualization, Data Curation, Formal Analysis, Funding Acquisition, Investigation, Methodology, Project Administration, Writing – Original Draft Preparation Sabrina Das Roles: Investigation, Writing – Review & Editing Roles: Investigation, Writing – Review & Editing Kate Stringer Roles: Investigation, Writing – Review & Editing Roles: Investigation, Writing – Review & Editing Emma Spillane Roles: Conceptualization, Investigation, Writing – Review & Editing Roles: Conceptualization, Investigation, Writing – Review & Editing Amy Meadowcroft Roles: Investigation, Writing – Review & Editing Roles: Investigation, Writing – Review & Editing Siân Davies Roles: Data Curation, Validation, Writing – Review & Editing Roles: Data Curation, Validation, Writing – Review & Editing Jacana Bresson Roles: Data Curation, Project Administration, Validation, Writing – Review & Editing Roles: Data Curation, Project Administration, Validation, Writing – Review & Editing Alice Hodder Roles: Formal Analysis, Validation Roles: Formal Analysis, Validation Jasmine Kang Roles: Formal Analysis, Validation Roles: Formal Analysis, Validation Competing interests SW and ES are co-Directors of Breech Birth Network, Community Interest Company, a not-for-profit social enterprise that delivers VBB training and supports research. They and other members of the OptiBreech Collaborative have received teaching fees and expenses for providing breech training. Profits from these teaching activities are used to fund further research and teaching activities. Grant information This project is funded by the National Institute for Health and Care Research (NIHR) (Grant number: NIHR300582). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Article Versions (2) Copyright © 2025 Walker S et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. metrics VIEWS $counts.viewCount downloads Citations CITE how to cite this article Walker S, Das S, Stringer K et al. How safe is it to plan a vaginal breech birth with OptiBreech collaborative care?: analysis of cumulative data within the OptiBreech Multiple Trials Cohort [version 2; peer review: 2 approved, 1 approved with reservations]. NIHR Open Res 2025, 3:61 (https://doi.org/10.3310/nihropenres.13500.2) NOTE: If applicable, it is important to ensure the information in square brackets after the title is included in all citations of this article. track receive updates on this article Track an article to receive email alerts on any updates to this article. Current Reviewer Status: ? Key to Reviewer Statuses VIEW HIDE ApprovedThe paper is scientifically sound in its current form and only minor, if any, improvements are suggested Approved with reservations A number of small changes, sometimes more significant revisions are required to address specific details and improve the papers academic merit. Not approvedFundamental flaws in the paper seriously undermine the findings and conclusions Version 2 VERSION 2 PUBLISHED 14 Nov 2025 Revised Views 0 How to cite this report: Barrowclough J. Reviewer Report For: How safe is it to plan a vaginal breech birth with OptiBreech collaborative care?: analysis of cumulative data within the OptiBreech Multiple Trials Cohort [version 2; peer review: 2 approved, 1 approved with reservations]. NIHR Open Res 2025, 3:61 (https://doi.org/10.3310/nihropenres.15390.r38349) The direct URL for this report is: https://openresearch.nihr.ac.uk/articles/3-61/v2#referee-response-38349 https://openresearch.nihr.ac.uk/articles/3-61/v2#referee-response-38349 NOTE: it is important to ensure the information in square brackets after the title is included in this citation. Reviewer Report 09 Dec 2025 Approved VIEWS 0 For original research, this means that the experimental design, including controls and methods, is ... Continue reading I confirm that I have read this submission and believe that I have an appropriate level of expertise to confirm that it is of an acceptable scientific standard. Close For original research, this means that the experimental design, including controls and methods, is adequate; results are presented accurately and the conclusions are justified and supported by the data” Competing Interests: No competing interests were disclosed. CITE HOW TO CITE THIS REPORT Barrowclough J. Reviewer Report For: How safe is it to plan a vaginal breech birth with OptiBreech collaborative care?: analysis of cumulative data within the OptiBreech Multiple Trials Cohort [version 2; peer review: 2 approved, 1 approved with reservations]. NIHR Open Res 2025, 3:61 (https://doi.org/10.3310/nihropenres.15390.r38349) The direct URL for this report is: https://openresearch.nihr.ac.uk/articles/3-61/v2#referee-response-38349 https://openresearch.nihr.ac.uk/articles/3-61/v2#referee-response-38349 NOTE: it is important to ensure the information in square brackets after the title is included in all citations of this article. Version 1 VERSION 1 PUBLISHED 23 Nov 2023 Views 0 How to cite this report: Schafer R. Reviewer Report For: How safe is it to plan a vaginal breech birth with OptiBreech collaborative care?: analysis of cumulative data within the OptiBreech Multiple Trials Cohort [version 2; peer review: 2 approved, 1 approved with reservations]. NIHR Open Res 2025, 3:61 (https://doi.org/10.3310/nihropenres.14650.r31049) The direct URL for this report is: https://openresearch.nihr.ac.uk/articles/3-61/v1#referee-response-31049 https://openresearch.nihr.ac.uk/articles/3-61/v1#referee-response-31049 NOTE: it is important to ensure the information in square brackets after the title is included in this citation. Reviewer Report 08 Apr 2024 Approved with Reservations VIEWS 0 Thank you for the invitation to review this original research article entitled, “How safe is it to plan a vaginal breech birth with OptiBreech collaborative care?” This publication provides an interim analysis of maternal and neonatal outcomes in a prospective ... Continue reading I confirm that I have read this submission and believe that I have an appropriate level of expertise to confirm that it is of an acceptable scientific standard, however I have significant reservations, as outlined above. Close Thank you for the invitation to review this original research article entitled, “How safe is it to plan a vaginal breech birth with OptiBreech collaborative care?” This publication provides an interim analysis of maternal and neonatal outcomes in a prospective trial of women planning a vaginal breech birth who received either standard NHS or OptiBreech care (including both randomized and non-randomized cohorts). Although the sample size is too small to detect meaningful differences in rare outcomes, the descriptive data are useful to inform future research efforts and guide decision-making regarding integration of this care model into the health system. The research topic is timely and important, and the study methodology is appropriate to the research questions and thoroughly described. Suggestions for increased detail and clarity to the methods/analysis to ensure reproducibility are provided below. Ethical standards for consent and participant involvement have been met. Equity analyses were included to assess accessibility and differences in outcomes for persons from minoritized groups. The authors should be commended on undertaking this important research effort to ensure that pregnant and birthing people with a breech fetus have options for high-quality care and informed choice for mode of birth. The following suggestions and questions might be considered to guide revisions and further strengthen this manuscript:

Additional information recommended to include: The research topic is timely and important, and the study methodology is appropriate to the research questions and thoroughly described. Suggestions for increased detail and clarity to the methods/analysis to ensure reproducibility are provided below. Ethical standards for consent and participant involvement have been met. Equity analyses were included to assess accessibility and differences in outcomes for persons from minoritized groups. The authors should be commended on undertaking this important research effort to ensure that pregnant and birthing people with a breech fetus have options for high-quality care and informed choice for mode of birth. The following suggestions and questions might be considered to guide revisions and further strengthen this manuscript:

- Use of gendered language. This publication is inconsistent in its use of gendered (i.e., “women” and “mothers”) and gender-inclusive terminology (i.e., “birthing people”). Furthermore, the authors state that “recruitment focused on women….” Does this mean that pregnant individuals who did not identify as women were intentionally not recruited? I would suggest the authors consider the use of gendered and gender-inclusive terminology throughout to accurately reflect the study protocol and, to the fullest extent possible, be inclusive with persons with diverse gender identities. - Confusing/unclear statements. (1) The authors state, “Balancing these risks [of surgical delivery and birth trauma] through person-centred care, centred on the person’s values and life context, is improved when obstetricians and midwives have skill and experience in vaginal breech birth (VBB).” Although I wholeheartedly agree in the importance of person-centered care for vaginal breech birth, it is unclear to me how the incorporation of PCC will improve the balance of surgical risks and trauma based on provider experience. Further explanation would be helpful. (2) The authors state, “Current NHS strategies to reduce risk focus on reducing the numbers of VBBs, through external cephalic version (ECV, turning the baby head-down) and/or planned caesarean birth (CB). An unintended effect has been decline in health care professionals’ skills.” I assume by “health professionals’ skills,” the authors mean those skills specific to vaginal breech birth? Such policies would logically increase providers’ skills in ECV, so further clarification would be useful. (3) The authors state, “This strategy has reduced the VBBs we can anticipate, resulting in a lack of learning opportunities for staff to safely manage those we cannot predict.” Do the authors mean that this strategy has reduced the number of vaginal breech births planned antenatally? I would hope that skilled birth attendants would be able to determine fetal position in labor prior to onset of second stage so that most vaginal breech births would be anticipated/predicted in the intrapartum setting. This statement is especially confusing given that the OptiBreech model includes those breech presentations discovered during labor. Additional information recommended to include: - This publication would benefit from inclusion of a clear definition of “standard care” and the ways in which OptiBreech care is different to orient the reader who may not be familiar with UK NHS and OptiBreech standards. - I would encourage the study authors to provide more specific exclusion criteria regarding “absolute reason for caesarean section” to list all relevant conditions that warranted exclusion from the study cohort. - There is no mention of labor induction or augmentation. The authors might consider adding information about labor management guidelines and the use of induction or augmentation across cohorts. - The manuscript states, “Generally, they were offered ECV as a first-line intervention …” Although Table 5 presents data regarding ECV, it is unclear how many participants were offered ECV, rationale for those that were not offered, what percent attempted the procedure, and rates of success in resulting in cephalic presentation at onset of labor. - The manuscript states that “professionals with advanced training in physiological breech birth attend VBBs whenever possible.” The lack of a clinician experienced in vaginal breech birth at all births in OptiBreech care is concerning given that best available evidence and consensus clinical practice recommendations specify the requirement of an experienced clinician for optimal health outcomes and, as this manuscript notes, there are wide variations in provider experience with regard to breech birth. It is unclear if the authors are implying by “advanced training” that clinicians had completed OptiBreech training or if other forms of breech skills training would qualify. Additional information about the education/training and level of experience of attendants should be described in greater detail. - The authors have reported outcomes based on type of breech presentation as either (a) extended/frank or (b) any other or uncertain. To provide more meaningful comparison, I would suggest removing “uncertain” presentations from the “any other” group to create a third category, since “uncertain” could also include extended/frank presentations. - The authors list both “vaginal breech birth” and “forceps breech birth,” but it is unclear if forceps is a subset of vaginal breech birth or if the former category includes only spontaneous vaginal births. - Could rationale for in-labour and pre-labour caesarean births be provided? - It appears the authors have used 3 cm dilation as the determining factor for differentiating “early” v. “active” labor. This is not consistent with standard definitions of active labor and should be explained. - Rates of episiotomy in OptiBreech care groups are quite high. Could the authors expound on the use of episiotomy in this model of care or provide rationale for the difference in episiotomy rates between cohorts? - The discussion section could be strengthened by including implications for patient education/counseling and recommendations for health policy aligned with the research questions. - Is the work clearly and accurately presented and does it cite the current literature? Yes - Is the study design appropriate and is the work technically sound? Yes - Are sufficient details of methods and analysis provided to allow replication by others? Partly - If applicable, is the statistical analysis and its interpretation appropriate? Yes - Are all the source data underlying the results available to ensure full reproducibility? Yes - Are the conclusions drawn adequately supported by the results? Yes Competing Interests: No competing interests were disclosed. Reviewer Expertise: Midwifery, perinatal and reproductive health, clinical decision-making, evidence-based practice, person-centered care, qualitative and mixed methods research CITE HOW TO CITE THIS REPORT Schafer R. Reviewer Report For: How safe is it to plan a vaginal breech birth with OptiBreech collaborative care?: analysis of cumulative data within the OptiBreech Multiple Trials Cohort [version 2; peer review: 2 approved, 1 approved with reservations]. NIHR Open Res 2025, 3:61 (https://doi.org/10.3310/nihropenres.14650.r31049) The direct URL for this report is: https://openresearch.nihr.ac.uk/articles/3-61/v1#referee-response-31049 https://openresearch.nihr.ac.uk/articles/3-61/v1#referee-response-31049 NOTE: it is important to ensure the information in square brackets after the title is included in all citations of this article. - Author Response 14 Nov 2025Shawn Walker, Women and Children's Health, King's College London, London, UK14 Nov 2025Author ResponseThank you for the invitation to review this original research article entitled, “How safe is it to plan a vaginal breech birth with OptiBreech collaborative care?” This publication provides an ... Continue reading Thank you for the invitation to review this original research article entitled, “How safe is it to plan a vaginal breech birth with OptiBreech collaborative care?” This publication provides an interim analysis of maternal and neonatal outcomes in a prospective trial of women planning a vaginal breech birth who received either standard NHS or OptiBreech care (including both randomized and non-randomized cohorts). Although the sample size is too small to detect meaningful differences in rare outcomes, the descriptive data are useful to inform future research efforts and guide decision-making regarding integration of this care model into the health system. The research topic is timely and important, and the study methodology is appropriate to the research questions and thoroughly described. Suggestions for increased detail and clarity to the methods/analysis to ensure reproducibility are provided below. Ethical standards for consent and participant involvement have been met. Equity analyses were included to assess accessibility and differences in outcomes for persons from minoritized groups. The authors should be commended on undertaking this important research effort to ensure that pregnant and birthing people with a breech fetus have options for high-quality care and informed choice for mode of birth. The following suggestions and questions might be considered to guide revisions and further strengthen this manuscript: Introduction- Use of gendered language. This publication is inconsistent in its use of gendered (i.e., “women” and “mothers”) and gender-inclusive terminology (i.e., “birthing people”). Furthermore, the authors state that “recruitment focused on women….” Does this mean that pregnant individuals who did not identify as women were intentionally not recruited? I would suggest the authors consider the use of gendered and gender-inclusive terminology throughout to accurately reflect the study protocol and, to the fullest extent possible, be inclusive with persons with diverse gender identities. We have added a clarifying statement. As a general rule throughout the OptiBreech research, after working with our PPIE group, we use sex-specific terminology and acknowledge the need to be inclusive of gender-diverse individuals as well. We have tried to strike a balance of signalling our desire to respect diverse gender identities, while also being clear and concise. - Confusing/unclear statements. (1) The authors state, “Balancing these risks [of surgical delivery and birth trauma] through person-centred care, centred on the person’s values and life context, is improved when obstetricians and midwives have skill and experience in vaginal breech birth (VBB).” Although I wholeheartedly agree in the importance of person-centered care for vaginal breech birth, it is unclear to me how the incorporation of PCC will improve the balance of surgical risks and trauma based on provider experience. Further explanation would be helpful. Further explanation has been added. Providers cannot offer the choice of a VBBs if they do not have the skills to do so safety, but due to the way services are currently delivered in standard services, experience in VBB is difficult to acquire. - (2) The authors state, “Current NHS strategies to reduce risk focus on reducing the numbers of VBBs, through external cephalic version (ECV, turning the baby head-down) and/or planned caesarean birth (CB). An unintended effect has been decline in health care professionals’ skills.” I assume by “health professionals’ skills,” the authors mean those skills specific to vaginal breech birth? Such policies would logically increase providers’ skills in ECV, so further clarification would be useful. VBB added for clarity. - (3) The authors state, “This strategy has reduced the VBBs we can anticipate, resulting in a lack of learning opportunities for staff to safely manage those we cannot predict.” Do the authors mean that this strategy has reduced the number of vaginal breech births planned antenatally? I would hope that skilled birth attendants would be able to determine fetal position in labor prior to onset of second stage so that most vaginal breech births would be anticipated/predicted in the intrapartum setting. This statement is especially confusing given that the OptiBreech model includes those breech presentations discovered during labor. Unfortunately, all available studies on the accuracy of palpation indicate that it is not consistently accurate, even with highly experienced attendants. Without universal ultrasound scans, the rate of diagnosis in labour is about 20%. Even with universal ultrasound, unstable lies mean the occasional breech presentation will be discovered in labour, and a small number of fetuses will turn in labour. Study protocol Additional information recommended to include:- This publication would benefit from inclusion of a clear definition of “standard care” and the ways in which OptiBreech care is different to orient the reader who may not be familiar with UK NHS and OptiBreech standards. We have clarified that our description of OptiBreech care is based on the ways it differs from standard care.- I would encourage the study authors to provide more specific exclusion criteria regarding “absolute reason for caesarean section” to list all relevant conditions that warranted exclusion from the study cohort. Thank you for this suggestion. The exclusion criteria are replicated here verbatim from the protocol. We acknowledge there may be differences in perception around what constitutes an absolute reason for caesarean section and will consider this for the future. - There is no mention of labor induction or augmentation. The authors might consider adding information about labor management guidelines and the use of induction or augmentation across cohorts. We do not currently have a guideline on this, and practice varied from site to site. The nature of the intervention – an experienced team – meant that some more experienced team were comfortable with this, and some were not. We are currently conducting a systematic review on outcomes for induced breech labours, and we hope to report the small amount of data we have where this occurred separately, in preparation for a study on this specific topic. - The manuscript states, “Generally, they were offered ECV as a first-line intervention …” Although Table 5 presents data regarding ECV, it is unclear how many participants were offered ECV, rationale for those that were not offered, what percent attempted the procedure, and rates of success in resulting in cephalic presentation at onset of labor. While we can understand the interest in this data, our focus in this study was on the offer of VBB and its outcomes. These were not among the outcome we prospectively aimed to report. - The manuscript states that “professionals with advanced training in physiological breech birth attend VBBs whenever possible.” The lack of a clinician experienced in vaginal breech birth at all births in OptiBreech care is concerning given that best available evidence and consensus clinical practice recommendations specify the requirement of an experienced clinician for optimal health outcomes and, as this manuscript notes, there are wide variations in provider experience with regard to breech birth. This is correct – the evidence indicates that an experienced clinician improves outcomes. This is one of the first studies to use objective criteria to determine ‘experienced,’ based on previous consensus research. One of the main barriers to offering women the choice of VBB is the inconsistency with which an experienced provider can be in attendance, and the inability to guarantee their presence. Despite our best efforts, due to the unpredictability of labour, we were not able to guarantee this either – for example, at least one precipitous labour occurred with no attendant at home. What we can do is to offer women information on the likelihood that an attendant with training and experience would be in attendance, so that they can make an informed choice about whether to proceed. In this revision, we have reported the experience levels of attendants as recorded. - It is unclear if the authors are implying by “advanced training” that clinicians had completed OptiBreech training or if other forms of breech skills training would qualify. Additional information about the education/training and level of experience of attendants should be described in greater detail. In this sentence, we reference the evaluations of the physiological breech birth training programme attendants had completed. The syllabus for the evaluated training is included in those publications, for replication purposes. Experience levels are reported in this revision. Results- The authors have reported outcomes based on type of breech presentation as either (a) extended/frank or (b) any other or uncertain. To provide more meaningful comparison, I would suggest removing “uncertain” presentations from the “any other” group to create a third category, since “uncertain” could also include extended/frank presentations. Our study was designed with extended or non-extended/flexed as the two minimisation categories. When we discovered that occasionally the type of breech was not identified, we conferred with our PIs about how to handle this, and this was the conclusion that was drawn. Uncertain presentations were therefore not reported separately and cannot be with the data we hold. - The authors list both “vaginal breech birth” and “forceps breech birth,” but it is unclear if forceps is a subset of vaginal breech birth or if the former category includes only spontaneous vaginal births. Further clarification added in keys below tables. - Could rationale for in-labour and pre-labour caesarean births be provided? We have incorporated the latest guidance on describing types of birth, based on the Re:Birth project, led by the RCM. https://rcm.org.uk/rebirth/ We have clarified in the key tables what each phrase includes, for clarity. - It appears the authors have used 3 cm dilation as the determining factor for differentiating “early” v. “active” labor. This is not consistent with standard definitions of active labor and should be explained. We have now included a justification, which is that we used the same categories as those used in the Term Breech Trial for consistency. All births included in these categories were vaginal births, despite a caesarean birth being initially planned, suggesting that they were indeed in active labour when diagnosed. - Rates of episiotomy in OptiBreech care groups are quite high. Could the authors expound on the use of episiotomy in this model of care or provide rationale for the difference in episiotomy rates between cohorts? In this publication, we have focused on reporting the outcomes. There are many details that need more time and space to unpick and examine more closely. We agree, this is one of these. The higher rate of episiotomy compared to cephalic births is consistent with all other studies that report perineal outcomes for both cohorts. Discussion- The discussion section could be strengthened by including implications for patient education/counseling and recommendations for health policy aligned with the research questions. As this was pilot/feasibility work, we are reluctant to make premature recommendations for counselling and policy changes. Our first priority is to obtain the funding to conduct a substantive study that would credibly result in data to inform policy decisions. Thank you for the opportunity to review this important research. Thank you for your thoughtful and considered review, and your kind words.Thank you for the invitation to review this original research article entitled, “How safe is it to plan a vaginal breech birth with OptiBreech collaborative care?” This publication provides an interim analysis of maternal and neonatal outcomes in a prospective trial of women planning a vaginal breech birth who received either standard NHS or OptiBreech care (including both randomized and non-randomized cohorts). Although the sample size is too small to detect meaningful differences in rare outcomes, the descriptive data are useful to inform future research efforts and guide decision-making regarding integration of this care model into the health system.Competing Interests: SW and ES are co-Directors of Breech Birth Network, an asset-locked, not-for-profit Community Interest Company that owns the Intellectual Property for the Physiological Breech Birth training materials used in this study. Almost all members of the OptiBreech Collaborative have contributed to teaching on this course and have received modest payments and expenses for doing so. Close The research topic is timely and important, and the study methodology is appropriate to the research questions and thoroughly described. Suggestions for increased detail and clarity to the methods/analysis to ensure reproducibility are provided below. Ethical standards for consent and participant involvement have been met. Equity analyses were included to assess accessibility and differences in outcomes for persons from minoritized groups. The authors should be commended on undertaking this important research effort to ensure that pregnant and birthing people with a breech fetus have options for high-quality care and informed choice for mode of birth. The following suggestions and questions might be considered to guide revisions and further strengthen this manuscript: Introduction- Use of gendered language. This publication is inconsistent in its use of gendered (i.e., “women” and “mothers”) and gender-inclusive terminology (i.e., “birthing people”). Furthermore, the authors state that “recruitment focused on women….” Does this mean that pregnant individuals who did not identify as women were intentionally not recruited? I would suggest the authors consider the use of gendered and gender-inclusive terminology throughout to accurately reflect the study protocol and, to the fullest extent possible, be inclusive with persons with diverse gender identities. We have added a clarifying statement. As a general rule throughout the OptiBreech research, after working with our PPIE group, we use sex-specific terminology and acknowledge the need to be inclusive of gender-diverse individuals as well. We have tried to strike a balance of signalling our desire to respect diverse gender identities, while also being clear and concise. - Confusing/unclear statements. (1) The authors state, “Balancing these risks [of surgical delivery and birth trauma] through person-centred care, centred on the person’s values and life context, is improved when obstetricians and midwives have skill and experience in vaginal breech birth (VBB).” Although I wholeheartedly agree in the importance of person-centered care for vaginal breech birth, it is unclear to me how the incorporation of PCC will improve the balance of surgical risks and trauma based on provider experience. Further explanation would be helpful. Further explanation has been added. Providers cannot offer the choice of a VBBs if they do not have the skills to do so safety, but due to the way services are currently delivered in standard services, experience in VBB is difficult to acquire. - (2) The authors state, “Current NHS strategies to reduce risk focus on reducing the numbers of VBBs, through external cephalic version (ECV, turning the baby head-down) and/or planned caesarean birth (CB). An unintended effect has been decline in health care professionals’ skills.” I assume by “health professionals’ skills,” the authors mean those skills specific to vaginal breech birth? Such policies would logically increase providers’ skills in ECV, so further clarification would be useful. VBB added for clarity. - (3) The authors state, “This strategy has reduced the VBBs we can anticipate, resulting in a lack of learning opportunities for staff to safely manage those we cannot predict.” Do the authors mean that this strategy has reduced the number of vaginal breech births planned antenatally? I would hope that skilled birth attendants would be able to determine fetal position in labor prior to onset of second stage so that most vaginal breech births would be anticipated/predicted in the intrapartum setting. This statement is especially confusing given that the OptiBreech model includes those breech presentations discovered during labor. Unfortunately, all available studies on the accuracy of palpation indicate that it is not consistently accurate, even with highly experienced attendants. Without universal ultrasound scans, the rate of diagnosis in labour is about 20%. Even with universal ultrasound, unstable lies mean the occasional breech presentation will be discovered in labour, and a small number of fetuses will turn in labour. Study protocol Additional information recommended to include:- This publication would benefit from inclusion of a clear definition of “standard care” and the ways in which OptiBreech care is different to orient the reader who may not be familiar with UK NHS and OptiBreech standards. We have clarified that our description of OptiBreech care is based on the ways it differs from standard care.- I would encourage the study authors to provide more specific exclusion criteria regarding “absolute reason for caesarean section” to list all relevant conditions that warranted exclusion from the study cohort. Thank you for this suggestion. The exclusion criteria are replicated here verbatim from the protocol. We acknowledge there may be differences in perception around what constitutes an absolute reason for caesarean section and will consider this for the future. - There is no mention of labor induction or augmentation. The authors might consider adding information about labor management guidelines and the use of induction or augmentation across cohorts. We do not currently have a guideline on this, and practice varied from site to site. The nature of the intervention – an experienced team – meant that some more experienced team were comfortable with this, and some were not. We are currently conducting a systematic review on outcomes for induced breech labours, and we hope to report the small amount of data we have where this occurred separately, in preparation for a study on this specific topic. - The manuscript states, “Generally, they were offered ECV as a first-line intervention …” Although Table 5 presents data regarding ECV, it is unclear how many participants were offered ECV, rationale for those that were not offered, what percent attempted the procedure, and rates of success in resulting in cephalic presentation at onset of labor. While we can understand the interest in this data, our focus in this study was on the offer of VBB and its outcomes. These were not among the outcome we prospectively aimed to report. - The manuscript states that “professionals with advanced training in physiological breech birth attend VBBs whenever possible.” The lack of a clinician experienced in vaginal breech birth at all births in OptiBreech care is concerning given that best available evidence and consensus clinical practice recommendations specify the requirement of an experienced clinician for optimal health outcomes and, as this manuscript notes, there are wide variations in provider experience with regard to breech birth. This is correct – the evidence indicates that an experienced clinician improves outcomes. This is one of the first studies to use objective criteria to determine ‘experienced,’ based on previous consensus research. One of the main barriers to offering women the choice of VBB is the inconsistency with which an experienced provider can be in attendance, and the inability to guarantee their presence. Despite our best efforts, due to the unpredictability of labour, we were not able to guarantee this either – for example, at least one precipitous labour occurred with no attendant at home. What we can do is to offer women information on the likelihood that an attendant with training and experience would be in attendance, so that they can make an informed choice about whether to proceed. In this revision, we have reported the experience levels of attendants as recorded. - It is unclear if the authors are implying by “advanced training” that clinicians had completed OptiBreech training or if other forms of breech skills training would qualify. Additional information about the education/training and level of experience of attendants should be described in greater detail. In this sentence, we reference the evaluations of the physiological breech birth training programme attendants had completed. The syllabus for the evaluated training is included in those publications, for replication purposes. Experience levels are reported in this revision. Results- The authors have reported outcomes based on type of breech presentation as either (a) extended/frank or (b) any other or uncertain. To provide more meaningful comparison, I would suggest removing “uncertain” presentations from the “any other” group to create a third category, since “uncertain” could also include extended/frank presentations. Our study was designed with extended or non-extended/flexed as the two minimisation categories. When we discovered that occasionally the type of breech was not identified, we conferred with our PIs about how to handle this, and this was the conclusion that was drawn. Uncertain presentations were therefore not reported separately and cannot be with the data we hold. - The authors list both “vaginal breech birth” and “forceps breech birth,” but it is unclear if forceps is a subset of vaginal breech birth or if the former category includes only spontaneous vaginal births. Further clarification added in keys below tables. - Could rationale for in-labour and pre-labour caesarean births be provided? We have incorporated the latest guidance on describing types of birth, based on the Re:Birth project, led by the RCM. https://rcm.org.uk/rebirth/ We have clarified in the key tables what each phrase includes, for clarity. - It appears the authors have used 3 cm dilation as the determining factor for differentiating “early” v. “active” labor. This is not consistent with standard definitions of active labor and should be explained. We have now included a justification, which is that we used the same categories as those used in the Term Breech Trial for consistency. All births included in these categories were vaginal births, despite a caesarean birth being initially planned, suggesting that they were indeed in active labour when diagnosed. - Rates of episiotomy in OptiBreech care groups are quite high. Could the authors expound on the use of episiotomy in this model of care or provide rationale for the difference in episiotomy rates between cohorts? In this publication, we have focused on reporting the outcomes. There are many details that need more time and space to unpick and examine more closely. We agree, this is one of these. The higher rate of episiotomy compared to cephalic births is consistent with all other studies that report perineal outcomes for both cohorts. Discussion- The discussion section could be strengthened by including implications for patient education/counseling and recommendations for health policy aligned with the research questions. As this was pilot/feasibility work, we are reluctant to make premature recommendations for counselling and policy changes. Our first priority is to obtain the funding to conduct a substantive study that would credibly result in data to inform policy decisions. Thank you for the opportunity to review this important research. Thank you for your thoughtful and considered review, and your kind words. COMMENTS ON THIS REPORT - Author Response 14 Nov 2025Shawn Walker, Women and Children's Health, King's College London, London, UK14 Nov 2025Author ResponseThank you for the invitation to review this original research article entitled, “How safe is it to plan a vaginal breech birth with OptiBreech collaborative care?” This publication provides an ... Continue reading Thank you for the invitation to review this original research article entitled, “How safe is it to plan a vaginal breech birth with OptiBreech collaborative care?” This publication provides an interim analysis of maternal and neonatal outcomes in a prospective trial of women planning a vaginal breech birth who received either standard NHS or OptiBreech care (including both randomized and non-randomized cohorts). Although the sample size is too small to detect meaningful differences in rare outcomes, the descriptive data are useful to inform future research efforts and guide decision-making regarding integration of this care model into the health system. The research topic is timely and important, and the study methodology is appropriate to the research questions and thoroughly described. Suggestions for increased detail and clarity to the methods/analysis to ensure reproducibility are provided below. Ethical standards for consent and participant involvement have been met. Equity analyses were included to assess accessibility and differences in outcomes for persons from minoritized groups. The authors should be commended on undertaking this important research effort to ensure that pregnant and birthing people with a breech fetus have options for high-quality care and informed choice for mode of birth. The following suggestions and questions might be considered to guide revisions and further strengthen this manuscript: Introduction- Use of gendered language. This publication is inconsistent in its use of gendered (i.e., “women” and “mothers”) and gender-inclusive terminology (i.e., “birthing people”). Furthermore, the authors state that “recruitment focused on women….” Does this mean that pregnant individuals who did not identify as women were intentionally not recruited? I would suggest the authors consider the use of gendered and gender-inclusive terminology throughout to accurately reflect the study protocol and, to the fullest extent possible, be inclusive with persons with diverse gender identities. We have added a clarifying statement. As a general rule throughout the OptiBreech research, after working with our PPIE group, we use sex-specific terminology and acknowledge the need to be inclusive of gender-diverse individuals as well. We have tried to strike a balance of signalling our desire to respect diverse gender identities, while also being clear and concise. - Confusing/unclear statements. (1) The authors state, “Balancing these risks [of surgical delivery and birth trauma] through person-centred care, centred on the person’s values and life context, is improved when obstetricians and midwives have skill and experience in vaginal breech birth (VBB).” Although I wholeheartedly agree in the importance of person-centered care for vaginal breech birth, it is unclear to me how the incorporation of PCC will improve the balance of surgical risks and trauma based on provider experience. Further explanation would be helpful. Further explanation has been added. Providers cannot offer the choice of a VBBs if they do not have the skills to do so safety, but due to the way services are currently delivered in standard services, experience in VBB is difficult to acquire. - (2) The authors state, “Current NHS strategies to reduce risk focus on reducing the numbers of VBBs, through external cephalic version (ECV, turning the baby head-down) and/or planned caesarean birth (CB). An unintended effect has been decline in health care professionals’ skills.” I assume by “health professionals’ skills,” the authors mean those skills specific to vaginal breech birth? Such policies would logically increase providers’ skills in ECV, so further clarification would be useful. VBB added for clarity. - (3) The authors state, “This strategy has reduced the VBBs we can anticipate, resulting in a lack of learning opportunities for staff to safely manage those we cannot predict.” Do the authors mean that this strategy has reduced the number of vaginal breech births planned antenatally? I would hope that skilled birth attendants would be able to determine fetal position in labor prior to onset of second stage so that most vaginal breech births would be anticipated/predicted in the intrapartum setting. This statement is especially confusing given that the OptiBreech model includes those breech presentations discovered during labor. Unfortunately, all available studies on the accuracy of palpation indicate that it is not consistently accurate, even with highly experienced attendants. Without universal ultrasound scans, the rate of diagnosis in labour is about 20%. Even with universal ultrasound, unstable lies mean the occasional breech presentation will be discovered in labour, and a small number of fetuses will turn in labour. Study protocol Additional information recommended to include:- This publication would benefit from inclusion of a clear definition of “standard care” and the ways in which OptiBreech care is different to orient the reader who may not be familiar with UK NHS and OptiBreech standards. We have clarified that our description of OptiBreech care is based on the ways it differs from standard care.- I would encourage the study authors to provide more specific exclusion criteria regarding “absolute reason for caesarean section” to list all relevant conditions that warranted exclusion from the study cohort. Thank you for this suggestion. The exclusion criteria are replicated here verbatim from the protocol. We acknowledge there may be differences in perception around what constitutes an absolute reason for caesarean section and will consider this for the future. - There is no mention of labor induction or augmentation. The authors might consider adding information about labor management guidelines and the use of induction or augmentation across cohorts. We do not currently have a guideline on this, and practice varied from site to site. The nature of the intervention – an experienced team – meant that some more experienced team were comfortable with this, and some were not. We are currently conducting a systematic review on outcomes for induced breech labours, and we hope to report the small amount of data we have where this occurred separately, in preparation for a study on this specific topic. - The manuscript states, “Generally, they were offered ECV as a first-line intervention …” Although Table 5 presents data regarding ECV, it is unclear how many participants were offered ECV, rationale for those that were not offered, what percent attempted the procedure, and rates of success in resulting in cephalic presentation at onset of labor. While we can understand the interest in this data, our focus in this study was on the offer of VBB and its outcomes. These were not among the outcome we prospectively aimed to report. - The manuscript states that “professionals with advanced training in physiological breech birth attend VBBs whenever possible.” The lack of a clinician experienced in vaginal breech birth at all births in OptiBreech care is concerning given that best available evidence and consensus clinical practice recommendations specify the requirement of an experienced clinician for optimal health outcomes and, as this manuscript notes, there are wide variations in provider experience with regard to breech birth. This is correct – the evidence indicates that an experienced clinician improves outcomes. This is one of the first studies to use objective criteria to determine ‘experienced,’ based on previous consensus research. One of the main barriers to offering women the choice of VBB is the inconsistency with which an experienced provider can be in attendance, and the inability to guarantee their presence. Despite our best efforts, due to the unpredictability of labour, we were not able to guarantee this either – for example, at least one precipitous labour occurred with no attendant at home. What we can do is to offer women information on the likelihood that an attendant with training and experience would be in attendance, so that they can make an informed choice about whether to proceed. In this revision, we have reported the experience levels of attendants as recorded. - It is unclear if the authors are implying by “advanced training” that clinicians had completed OptiBreech training or if other forms of breech skills training would qualify. Additional information about the education/training and level of experience of attendants should be described in greater detail. In this sentence, we reference the evaluations of the physiological breech birth training programme attendants had completed. The syllabus for the evaluated training is included in those publications, for replication purposes. Experience levels are reported in this revision. Results- The authors have reported outcomes based on type of breech presentation as either (a) extended/frank or (b) any other or uncertain. To provide more meaningful comparison, I would suggest removing “uncertain” presentations from the “any other” group to create a third category, since “uncertain” could also include extended/frank presentations. Our study was designed with extended or non-extended/flexed as the two minimisation categories. When we discovered that occasionally the type of breech was not identified, we conferred with our PIs about how to handle this, and this was the conclusion that was drawn. Uncertain presentations were therefore not reported separately and cannot be with the data we hold. - The authors list both “vaginal breech birth” and “forceps breech birth,” but it is unclear if forceps is a subset of vaginal breech birth or if the former category includes only spontaneous vaginal births. Further clarification added in keys below tables. - Could rationale for in-labour and pre-labour caesarean births be provided? We have incorporated the latest guidance on describing types of birth, based on the Re:Birth project, led by the RCM. https://rcm.org.uk/rebirth/ We have clarified in the key tables what each phrase includes, for clarity. - It appears the authors have used 3 cm dilation as the determining factor for differentiating “early” v. “active” labor. This is not consistent with standard definitions of active labor and should be explained. We have now included a justification, which is that we used the same categories as those used in the Term Breech Trial for consistency. All births included in these categories were vaginal births, despite a caesarean birth being initially planned, suggesting that they were indeed in active labour when diagnosed. - Rates of episiotomy in OptiBreech care groups are quite high. Could the authors expound on the use of episiotomy in this model of care or provide rationale for the difference in episiotomy rates between cohorts? In this publication, we have focused on reporting the outcomes. There are many details that need more time and space to unpick and examine more closely. We agree, this is one of these. The higher rate of episiotomy compared to cephalic births is consistent with all other studies that report perineal outcomes for both cohorts. Discussion- The discussion section could be strengthened by including implications for patient education/counseling and recommendations for health policy aligned with the research questions. As this was pilot/feasibility work, we are reluctant to make premature recommendations for counselling and policy changes. Our first priority is to obtain the funding to conduct a substantive study that would credibly result in data to inform policy decisions. Thank you for the opportunity to review this important research. Thank you for your thoughtful and considered review, and your kind words.Thank you for the invitation to review this original research article entitled, “How safe is it to plan a vaginal breech birth with OptiBreech collaborative care?” This publication provides an interim analysis of maternal and neonatal outcomes in a prospective trial of women planning a vaginal breech birth who received either standard NHS or OptiBreech care (including both randomized and non-randomized cohorts). Although the sample size is too small to detect meaningful differences in rare outcomes, the descriptive data are useful to inform future research efforts and guide decision-making regarding integration of this care model into the health system.Competing Interests: SW and ES are co-Directors of Breech Birth Network, an asset-locked, not-for-profit Community Interest Company that owns the Intellectual Property for the Physiological Breech Birth training materials used in this study. Almost all members of the OptiBreech Collaborative have contributed to teaching on this course and have received modest payments and expenses for doing so. Close The research topic is timely and important, and the study methodology is appropriate to the research questions and thoroughly described. Suggestions for increased detail and clarity to the methods/analysis to ensure reproducibility are provided below. Ethical standards for consent and participant involvement have been met. Equity analyses were included to assess accessibility and differences in outcomes for persons from minoritized groups. The authors should be commended on undertaking this important research effort to ensure that pregnant and birthing people with a breech fetus have options for high-quality care and informed choice for mode of birth. The following suggestions and questions might be considered to guide revisions and further strengthen this manuscript: Introduction- Use of gendered language. This publication is inconsistent in its use of gendered (i.e., “women” and “mothers”) and gender-inclusive terminology (i.e., “birthing people”). Furthermore, the authors state that “recruitment focused on women….” Does this mean that pregnant individuals who did not identify as women were intentionally not recruited? I would suggest the authors consider the use of gendered and gender-inclusive terminology throughout to accurately reflect the study protocol and, to the fullest extent possible, be inclusive with persons with diverse gender identities. We have added a clarifying statement. As a general rule throughout the OptiBreech research, after working with our PPIE group, we use sex-specific terminology and acknowledge the need to be inclusive of gender-diverse individuals as well. We have tried to strike a balance of signalling our desire to respect diverse gender identities, while also being clear and concise. - Confusing/unclear statements. (1) The authors state, “Balancing these risks [of surgical delivery and birth trauma] through person-centred care, centred on the person’s values and life context, is improved when obstetricians and midwives have skill and experience in vaginal breech birth (VBB).” Although I wholeheartedly agree in the importance of person-centered care for vaginal breech birth, it is unclear to me how the incorporation of PCC will improve the balance of surgical risks and trauma based on provider experience. Further explanation would be helpful. Further explanation has been added. Providers cannot offer the choice of a VBBs if they do not have the skills to do so safety, but due to the way services are currently delivered in standard services, experience in VBB is difficult to acquire. - (2) The authors state, “Current NHS strategies to reduce risk focus on reducing the numbers of VBBs, through external cephalic version (ECV, turning the baby head-down) and/or planned caesarean birth (CB). An unintended effect has been decline in health care professionals’ skills.” I assume by “health professionals’ skills,” the authors mean those skills specific to vaginal breech birth? Such policies would logically increase providers’ skills in ECV, so further clarification would be useful. VBB added for clarity. - (3) The authors state, “This strategy has reduced the VBBs we can anticipate, resulting in a lack of learning opportunities for staff to safely manage those we cannot predict.” Do the authors mean that this strategy has reduced the number of vaginal breech births planned antenatally? I would hope that skilled birth attendants would be able to determine fetal position in labor prior to onset of second stage so that most vaginal breech births would be anticipated/predicted in the intrapartum setting. This statement is especially confusing given that the OptiBreech model includes those breech presentations discovered during labor. Unfortunately, all available studies on the accuracy of palpation indicate that it is not consistently accurate, even with highly experienced attendants. Without universal ultrasound scans, the rate of diagnosis in labour is about 20%. Even with universal ultrasound, unstable lies mean the occasional breech presentation will be discovered in labour, and a small number of fetuses will turn in labour. Study protocol Additional information recommended to include:- This publication would benefit from inclusion of a clear definition of “standard care” and the ways in which OptiBreech care is different to orient the reader who may not be familiar with UK NHS and OptiBreech standards. We have clarified that our description of OptiBreech care is based on the ways it differs from standard care.- I would encourage the study authors to provide more specific exclusion criteria regarding “absolute reason for caesarean section” to list all relevant conditions that warranted exclusion from the study cohort. Thank you for this suggestion. The exclusion criteria are replicated here verbatim from the protocol. We acknowledge there may be differences in perception around what constitutes an absolute reason for caesarean section and will consider this for the future. - There is no mention of labor induction or augmentation. The authors might consider adding information about labor management guidelines and the use of induction or augmentation across cohorts. We do not currently have a guideline on this, and practice varied from site to site. The nature of the intervention – an experienced team – meant that some more experienced team were comfortable with this, and some were not. We are currently conducting a systematic review on outcomes for induced breech labours, and we hope to report the small amount of data we have where this occurred separately, in preparation for a study on this specific topic. - The manuscript states, “Generally, they were offered ECV as a first-line intervention …” Although Table 5 presents data regarding ECV, it is unclear how many participants were offered ECV, rationale for those that were not offered, what percent attempted the procedure, and rates of success in resulting in cephalic presentation at onset of labor. While we can understand the interest in this data, our focus in this study was on the offer of VBB and its outcomes. These were not among the outcome we prospectively aimed to report. - The manuscript states that “professionals with advanced training in physiological breech birth attend VBBs whenever possible.” The lack of a clinician experienced in vaginal breech birth at all births in OptiBreech care is concerning given that best available evidence and consensus clinical practice recommendations specify the requirement of an experienced clinician for optimal health outcomes and, as this manuscript notes, there are wide variations in provider experience with regard to breech birth. This is correct – the evidence indicates that an experienced clinician improves outcomes. This is one of the first studies to use objective criteria to determine ‘experienced,’ based on previous consensus research. One of the main barriers to offering women the choice of VBB is the inconsistency with which an experienced provider can be in attendance, and the inability to guarantee their presence. Despite our best efforts, due to the unpredictability of labour, we were not able to guarantee this either – for example, at least one precipitous labour occurred with no attendant at home. What we can do is to offer women information on the likelihood that an attendant with training and experience would be in attendance, so that they can make an informed choice about whether to proceed. In this revision, we have reported the experience levels of attendants as recorded. - It is unclear if the authors are implying by “advanced training” that clinicians had completed OptiBreech training or if other forms of breech skills training would qualify. Additional information about the education/training and level of experience of attendants should be described in greater detail. In this sentence, we reference the evaluations of the physiological breech birth training programme attendants had completed. The syllabus for the evaluated training is included in those publications, for replication purposes. Experience levels are reported in this revision. Results- The authors have reported outcomes based on type of breech presentation as either (a) extended/frank or (b) any other or uncertain. To provide more meaningful comparison, I would suggest removing “uncertain” presentations from the “any other” group to create a third category, since “uncertain” could also include extended/frank presentations. Our study was designed with extended or non-extended/flexed as the two minimisation categories. When we discovered that occasionally the type of breech was not identified, we conferred with our PIs about how to handle this, and this was the conclusion that was drawn. Uncertain presentations were therefore not reported separately and cannot be with the data we hold. - The authors list both “vaginal breech birth” and “forceps breech birth,” but it is unclear if forceps is a subset of vaginal breech birth or if the former category includes only spontaneous vaginal births. Further clarification added in keys below tables. - Could rationale for in-labour and pre-labour caesarean births be provided? We have incorporated the latest guidance on describing types of birth, based on the Re:Birth project, led by the RCM. https://rcm.org.uk/rebirth/ We have clarified in the key tables what each phrase includes, for clarity. - It appears the authors have used 3 cm dilation as the determining factor for differentiating “early” v. “active” labor. This is not consistent with standard definitions of active labor and should be explained. We have now included a justification, which is that we used the same categories as those used in the Term Breech Trial for consistency. All births included in these categories were vaginal births, despite a caesarean birth being initially planned, suggesting that they were indeed in active labour when diagnosed. - Rates of episiotomy in OptiBreech care groups are quite high. Could the authors expound on the use of episiotomy in this model of care or provide rationale for the difference in episiotomy rates between cohorts? In this publication, we have focused on reporting the outcomes. There are many details that need more time and space to unpick and examine more closely. We agree, this is one of these. The higher rate of episiotomy compared to cephalic births is consistent with all other studies that report perineal outcomes for both cohorts. Discussion- The discussion section could be strengthened by including implications for patient education/counseling and recommendations for health policy aligned with the research questions. As this was pilot/feasibility work, we are reluctant to make premature recommendations for counselling and policy changes. Our first priority is to obtain the funding to conduct a substantive study that would credibly result in data to inform policy decisions. Thank you for the opportunity to review this important research. Thank you for your thoughtful and considered review, and your kind words. Views 0 How to cite this report: Barrowclough J. Reviewer Report For: How safe is it to plan a vaginal breech birth with OptiBreech collaborative care?: analysis of cumulative data within the OptiBreech Multiple Trials Cohort [version 2; peer review: 2 approved, 1 approved with reservations]. NIHR Open Res 2025, 3:61 (https://doi.org/10.3310/nihropenres.14650.r31389) The direct URL for this report is: https://openresearch.nihr.ac.uk/articles/3-61/v1#referee-response-31389 https://openresearch.nihr.ac.uk/articles/3-61/v1#referee-response-31389 NOTE: it is important to ensure the information in square brackets after the title is included in this citation. Reviewer Report 01 Apr 2024 Approved with Reservations VIEWS 0 Congratulations on conducting the OptiBreech collaborative care study and documenting the comprehensive interim analysis that may lead to improved outcomes for women and their babies following breech presentation. I suggest some minor revisions and points to consider below. The manuscript ... Continue reading I confirm that I have read this submission and believe that I have an appropriate level of expertise to confirm that it is of an acceptable scientific standard, however I have significant reservations, as outlined above. Close Congratulations on conducting the OptiBreech collaborative care study and documenting the comprehensive interim analysis that may lead to improved outcomes for women and their babies following breech presentation. I suggest some minor revisions and points to consider below. The manuscript is well written but due to the multi-dimensional cohort, the reader may need extra clarification of these where relevant throughout the text. There appears to be some formatting issues for some words that include unnecessary spaces and dashes. More importantly there appear to be some errors in the tables and need for some data concerning adverse events to be presented in separate rows. Comments 1. Abstract:

It would be helpful to insert '(Table 8)', after first sentence of Results in the Abstract. It would help clarify the results if you insert the text '(all presentations)' after 'achieved a vaginal birth' in line one of Results. Please correct percentage 2/52 (3.7%) in Results - it should be 3.8%. Please clarify '...planned a cephalic birth'. Does this refer to women who initially had a breech presentation which later turned? Is so, consider inserting the words 'after breech turned' after the words 'cephalic birth.', if this is correct. 2. Methods: Procedures First paragraph- Please insert 'ECV' after 'declined' i.e. '...regarding mode of birth if declined [ECV].' Outcomes First paragraph - I suggest you insert ‘outcomes including:...’ after ‘short term’ Please insert '1-16' after 'Below each table' Statistical analysis In paragraph 5, please explain by what means a fetus was 'discovered' to be presenting breech in labour...' i.e. was this by confirmed by scan? Paragraph 6, Should PPI be PPIE? Please correct as needed, here and subsequently. Paragraph 6, clause 6), Perhaps rephrase as 'our PPI group was keen to ensure participants were not disadvantaged by nationality, ethnicity or skin colour’? and later consider using the term 'non-Caucasian British' or 'non-Caucasian-non British' in the tables. Was this a unanimous decision or a proportion of the PPI group? How many members were in the PPI group? Reference to skin colour in academic publications is not current practice, though I appreciate your point and Lancet citation with evidence of inequity based on skin colour. If you still intend to refer to colour, you may need to emphasis more why you are doing this, and use footnote for Table 1 to provide the Lancet citation after the first two rows under the heading 'Any other ethnic group'. 3. Results: The Key Questions that are addressed in each table is a novel and useful way to present the findings. However, the Results section could benefit with a summary of the findings similar to in your abstract, as it otherwise goes straight to the tables which are numerous. Tables Please capitalise the first letter of the first word for all outcomes throughout all tables. Table 1, I suggest you rephrase the heading 'Diagnosis prior to labour', to ‘Timing of diagnosis’, given row 2 under this heading refers to 'in labour...' Table 3, There should be a separate row for mortality. Please clarify why the legend describing the definition of severe morbidity, does not appear to be reflected in the numbers (%) provided for 'Severe neonatal morbidity/mortality prior to discharge.' - Please make it possible for the reader to see the numbers for the parts that make up this composite outcome. Please check all percentages in all tables.

The Discussion refers to relevant studies which align with the design of OptiBreech cohort study, and considerations for the OptiBreech guideline. Paragraph 3, the sentence 'We have therefore reported 200 prospective VBBs across three studies, with one serious adverse neonatal outcomes (0.5%)', is confusing. Please insert 'including the present study' after 'three studies' to improve clarity. (if this is what is meant). Second to last paragraph, first sentence, please explain what you mean by cultural change? Are you referring to the culture of labour care concerning the umbilical cord or other cultural changes? Thank you for undertaking and continuing this most important work, and your preparatory studies. Comments 1. Abstract:

It would be helpful to insert '(Table 8)', after first sentence of Results in the Abstract. It would help clarify the results if you insert the text '(all presentations)' after 'achieved a vaginal birth' in line one of Results. Please correct percentage 2/52 (3.7%) in Results - it should be 3.8%. Please clarify '...planned a cephalic birth'. Does this refer to women who initially had a breech presentation which later turned? Is so, consider inserting the words 'after breech turned' after the words 'cephalic birth.', if this is correct. 2. Methods: Procedures First paragraph- Please insert 'ECV' after 'declined' i.e. '...regarding mode of birth if declined [ECV].' Outcomes First paragraph - I suggest you insert ‘outcomes including:...’ after ‘short term’ Please insert '1-16' after 'Below each table' Statistical analysis In paragraph 5, please explain by what means a fetus was 'discovered' to be presenting breech in labour...' i.e. was this by confirmed by scan? Paragraph 6, Should PPI be PPIE? Please correct as needed, here and subsequently. Paragraph 6, clause 6), Perhaps rephrase as 'our PPI group was keen to ensure participants were not disadvantaged by nationality, ethnicity or skin colour’? and later consider using the term 'non-Caucasian British' or 'non-Caucasian-non British' in the tables. Was this a unanimous decision or a proportion of the PPI group? How many members were in the PPI group? Reference to skin colour in academic publications is not current practice, though I appreciate your point and Lancet citation with evidence of inequity based on skin colour. If you still intend to refer to colour, you may need to emphasis more why you are doing this, and use footnote for Table 1 to provide the Lancet citation after the first two rows under the heading 'Any other ethnic group'. 3. Results: The Key Questions that are addressed in each table is a novel and useful way to present the findings. However, the Results section could benefit with a summary of the findings similar to in your abstract, as it otherwise goes straight to the tables which are numerous. Tables Please capitalise the first letter of the first word for all outcomes throughout all tables. Table 1, I suggest you rephrase the heading 'Diagnosis prior to labour', to ‘Timing of diagnosis’, given row 2 under this heading refers to 'in labour...' Table 3, There should be a separate row for mortality. Please clarify why the legend describing the definition of severe morbidity, does not appear to be reflected in the numbers (%) provided for 'Severe neonatal morbidity/mortality prior to discharge.' - Please make it possible for the reader to see the numbers for the parts that make up this composite outcome. Please check all percentages in all tables.

The Discussion refers to relevant studies which align with the design of OptiBreech cohort study, and considerations for the OptiBreech guideline. Paragraph 3, the sentence 'We have therefore reported 200 prospective VBBs across three studies, with one serious adverse neonatal outcomes (0.5%)', is confusing. Please insert 'including the present study' after 'three studies' to improve clarity. (if this is what is meant). Second to last paragraph, first sentence, please explain what you mean by cultural change? Are you referring to the culture of labour care concerning the umbilical cord or other cultural changes? Thank you for undertaking and continuing this most important work, and your preparatory studies. - Is the work clearly and accurately presented and does it cite the current literature? Partly - Is the study design appropriate and is the work technically sound? Yes - Are sufficient details of methods and analysis provided to allow replication by others? Yes - If applicable, is the statistical analysis and its interpretation appropriate? Yes - Are all the source data underlying the results available to ensure full reproducibility? Partly - Are the conclusions drawn adequately supported by the results? Yes Competing Interests: No competing interests were disclosed. Reviewer Expertise: Fetal malposition; Use of maternal posture to improve health outcomes of fetal malposition for mothers and their babies. CITE HOW TO CITE THIS REPORT Barrowclough J. Reviewer Report For: How safe is it to plan a vaginal breech birth with OptiBreech collaborative care?: analysis of cumulative data within the OptiBreech Multiple Trials Cohort [version 2; peer review: 2 approved, 1 approved with reservations]. NIHR Open Res 2025, 3:61 (https://doi.org/10.3310/nihropenres.14650.r31389) The direct URL for this report is: https://openresearch.nihr.ac.uk/articles/3-61/v1#referee-response-31389 https://openresearch.nihr.ac.uk/articles/3-61/v1#referee-response-31389 NOTE: it is important to ensure the information in square brackets after the title is included in all citations of this article. - Author Response 14 Nov 2025Shawn Walker, Women and Children's Health, King's College London, London, UK14 Nov 2025Author ResponseCongratulations on conducting the OptiBreech collaborative care study and documenting the comprehensive interim analysis that may lead to improved outcomes for women and their babies following breech presentation. I suggest ... Continue reading Congratulations on conducting the OptiBreech collaborative care study and documenting the comprehensive interim analysis that may lead to improved outcomes for women and their babies following breech presentation. I suggest some minor revisions and points to consider below. The manuscript is well written but due to the multi-dimensional cohort, the reader may need extra clarification of these where relevant throughout the text. There appears to be some formatting issues for some words that include unnecessary spaces and dashes. More importantly there appear to be some errors in the tables and need for some data concerning adverse events to be presented in separate rows. Comments 1. Abstract:

It would be helpful to insert '(Table 8)', after first sentence of Results in the Abstract. It would help clarify the results if you insert the text '(all presentations)' after 'achieved a vaginal birth' in line one of Results. Author Response: Referring to a Table in an Abstract is not standard practice, so we have not done this. We feel that (all presentations) would be confusing in the Abstract without the benefit of further explanation. Please correct percentage 2/52 (3.7%) in Results - it should be 3.8%. Author Response: All results have been updated with the remaining data and double-checked. Please clarify '...planned a cephalic birth'. Does this refer to women who initially had a breech presentation which later turned? Is so, consider inserting the words 'after breech turned' after the words 'cephalic birth.', if this is correct. Author Response: We have added ‘after spontaneous version or external cephalic version’ for clarity 2. Methods: Procedures First paragraph- Please insert 'ECV' after 'declined' i.e. '...regarding mode of birth if declined [ECV].' Author Response: We have changed this to ‘if ECV failed or was declined’ for clarity. Outcomes First paragraph - I suggest you insert ‘outcomes including:...’ after ‘short term’ Please insert '1-16' after 'Below each table' Author Response: Changed as suggested. Statistical analysis In paragraph 5, please explain by what means a fetus was 'discovered' to be presenting breech in labour...' i.e. was this by confirmed by scan? Author Response: The word ‘discovered’ is one of the Inclusion criteria from the protocol, so cannot be altered. This discovery may be by ultrasound scan if time permits, but sometimes it is determined solely by vaginal examination or visualisation of the buttocks on the perineum. Paragraph 6, Should PPI be PPIE? Please correct as needed, here and subsequently. Author Response: We have searched for all instances of PPI and replaced with PPIE. Paragraph 6, clause 6), Perhaps rephrase as 'our PPI group was keen to ensure participants were not disadvantaged by nationality, ethnicity or skin colour’? and later consider using the term 'non-Caucasian British' or 'non-Caucasian-non British' in the tables. Was this a unanimous decision or a proportion of the PPI group? How many members were in the PPI group? Reference to skin colour in academic publications is not current practice, though I appreciate your point and Lancet citation with evidence of inequity based on skin colour. If you still intend to refer to colour, you may need to emphasis more why you are doing this, and use footnote for Table 1 to provide the Lancet citation after the first two rows under the heading 'Any other ethnic group'. Author Response: I cannot remember how many people were present when this was discussed, but the specific language used was suggested by a black member of research group, based on diversity reporting guidelines used in the UK. The group were unanimous that we needed to get over our discomfort of referring to skin colour and make it visible. We have added a reference to the Lancet article as suggested in the text. We have also added a further explanatory paragraph in the discussion. 3. Results: The Key Questions that are addressed in each table is a novel and useful way to present the findings. However, the Results section could benefit with a summary of the findings similar to in your abstract, as it otherwise goes straight to the tables which are numerous. Tables Please capitalise the first letter of the first word for all outcomes throughout all tables. Table 1, I suggest you rephrase the heading 'Diagnosis prior to labour', to ‘Timing of diagnosis’, given row 2 under this heading refers to 'in labour...' Author Response: Changed as suggested. Table 3, There should be a separate row for mortality. Author Response: This has been added to all neonatal outcome tables. Please clarify why the legend describing the definition of severe morbidity, does not appear to be reflected in the numbers (%) provided for 'Severe neonatal morbidity/mortality prior to discharge.' - Please make it possible for the reader to see the numbers for the parts that make up this composite outcome. Author Response: This has been added to all neonatal outcome tables. Please check all percentages in all tables. Author Response: These have been checked.

The Discussion refers to relevant studies which align with the design of OptiBreech cohort study, and considerations for the OptiBreech guideline. Paragraph 3, the sentence 'We have therefore reported 200 prospective VBBs across three studies, with one serious adverse neonatal outcomes (0.5%)', is confusing. Please insert 'including the present study' after 'three studies' to improve clarity. (if this is what is meant). Author Response: Changed as suggested. Second to last paragraph, first sentence, please explain what you mean by cultural change? Are you referring to the culture of labour care concerning the umbilical cord or other cultural changes? Author Response: We have changed the word ‘cultural’ to ‘clinical’ for clarity. Thank you for undertaking and continuing this most important work, and your preparatory studies. Thank you for your careful and considered review, and kind words.Congratulations on conducting the OptiBreech collaborative care study and documenting the comprehensive interim analysis that may lead to improved outcomes for women and their babies following breech presentation. I suggest some minor revisions and points to consider below. The manuscript is well written but due to the multi-dimensional cohort, the reader may need extra clarification of these where relevant throughout the text. There appears to be some formatting issues for some words that include unnecessary spaces and dashes. More importantly there appear to be some errors in the tables and need for some data concerning adverse events to be presented in separate rows.Competing Interests: SW and ES are co-Directors of Breech Birth Network, an asset-locked, not-for-profit Community Interest Company that owns the Intellectual Property for the Physiological Breech Birth training materials used in this study. Almost all members of the OptiBreech Collaborative have contributed to teaching on this course and have received modest payments and expenses for doing so. Close Comments 1. Abstract:

It would be helpful to insert '(Table 8)', after first sentence of Results in the Abstract. It would help clarify the results if you insert the text '(all presentations)' after 'achieved a vaginal birth' in line one of Results. Author Response: Referring to a Table in an Abstract is not standard practice, so we have not done this. We feel that (all presentations) would be confusing in the Abstract without the benefit of further explanation. Please correct percentage 2/52 (3.7%) in Results - it should be 3.8%. Author Response: All results have been updated with the remaining data and double-checked. Please clarify '...planned a cephalic birth'. Does this refer to women who initially had a breech presentation which later turned? Is so, consider inserting the words 'after breech turned' after the words 'cephalic birth.', if this is correct. Author Response: We have added ‘after spontaneous version or external cephalic version’ for clarity 2. Methods: Procedures First paragraph- Please insert 'ECV' after 'declined' i.e. '...regarding mode of birth if declined [ECV].' Author Response: We have changed this to ‘if ECV failed or was declined’ for clarity. Outcomes First paragraph - I suggest you insert ‘outcomes including:...’ after ‘short term’ Please insert '1-16' after 'Below each table' Author Response: Changed as suggested. Statistical analysis In paragraph 5, please explain by what means a fetus was 'discovered' to be presenting breech in labour...' i.e. was this by confirmed by scan? Author Response: The word ‘discovered’ is one of the Inclusion criteria from the protocol, so cannot be altered. This discovery may be by ultrasound scan if time permits, but sometimes it is determined solely by vaginal examination or visualisation of the buttocks on the perineum. Paragraph 6, Should PPI be PPIE? Please correct as needed, here and subsequently. Author Response: We have searched for all instances of PPI and replaced with PPIE. Paragraph 6, clause 6), Perhaps rephrase as 'our PPI group was keen to ensure participants were not disadvantaged by nationality, ethnicity or skin colour’? and later consider using the term 'non-Caucasian British' or 'non-Caucasian-non British' in the tables. Was this a unanimous decision or a proportion of the PPI group? How many members were in the PPI group? Reference to skin colour in academic publications is not current practice, though I appreciate your point and Lancet citation with evidence of inequity based on skin colour. If you still intend to refer to colour, you may need to emphasis more why you are doing this, and use footnote for Table 1 to provide the Lancet citation after the first two rows under the heading 'Any other ethnic group'. Author Response: I cannot remember how many people were present when this was discussed, but the specific language used was suggested by a black member of research group, based on diversity reporting guidelines used in the UK. The group were unanimous that we needed to get over our discomfort of referring to skin colour and make it visible. We have added a reference to the Lancet article as suggested in the text. We have also added a further explanatory paragraph in the discussion. 3. Results: The Key Questions that are addressed in each table is a novel and useful way to present the findings. However, the Results section could benefit with a summary of the findings similar to in your abstract, as it otherwise goes straight to the tables which are numerous. Tables Please capitalise the first letter of the first word for all outcomes throughout all tables. Table 1, I suggest you rephrase the heading 'Diagnosis prior to labour', to ‘Timing of diagnosis’, given row 2 under this heading refers to 'in labour...' Author Response: Changed as suggested. Table 3, There should be a separate row for mortality. Author Response: This has been added to all neonatal outcome tables. Please clarify why the legend describing the definition of severe morbidity, does not appear to be reflected in the numbers (%) provided for 'Severe neonatal morbidity/mortality prior to discharge.' - Please make it possible for the reader to see the numbers for the parts that make up this composite outcome. Author Response: This has been added to all neonatal outcome tables. Please check all percentages in all tables. Author Response: These have been checked.

The Discussion refers to relevant studies which align with the design of OptiBreech cohort study, and considerations for the OptiBreech guideline. Paragraph 3, the sentence 'We have therefore reported 200 prospective VBBs across three studies, with one serious adverse neonatal outcomes (0.5%)', is confusing. Please insert 'including the present study' after 'three studies' to improve clarity. (if this is what is meant). Author Response: Changed as suggested. Second to last paragraph, first sentence, please explain what you mean by cultural change? Are you referring to the culture of labour care concerning the umbilical cord or other cultural changes? Author Response: We have changed the word ‘cultural’ to ‘clinical’ for clarity. Thank you for undertaking and continuing this most important work, and your preparatory studies. Thank you for your careful and considered review, and kind words. COMMENTS ON THIS REPORT - Author Response 14 Nov 2025Shawn Walker, Women and Children's Health, King's College London, London, UK14 Nov 2025Author ResponseCongratulations on conducting the OptiBreech collaborative care study and documenting the comprehensive interim analysis that may lead to improved outcomes for women and their babies following breech presentation. I suggest ... Continue reading Congratulations on conducting the OptiBreech collaborative care study and documenting the comprehensive interim analysis that may lead to improved outcomes for women and their babies following breech presentation. I suggest some minor revisions and points to consider below. The manuscript is well written but due to the multi-dimensional cohort, the reader may need extra clarification of these where relevant throughout the text. There appears to be some formatting issues for some words that include unnecessary spaces and dashes. More importantly there appear to be some errors in the tables and need for some data concerning adverse events to be presented in separate rows. Comments 1. Abstract:

It would be helpful to insert '(Table 8)', after first sentence of Results in the Abstract. It would help clarify the results if you insert the text '(all presentations)' after 'achieved a vaginal birth' in line one of Results. Author Response: Referring to a Table in an Abstract is not standard practice, so we have not done this. We feel that (all presentations) would be confusing in the Abstract without the benefit of further explanation. Please correct percentage 2/52 (3.7%) in Results - it should be 3.8%. Author Response: All results have been updated with the remaining data and double-checked. Please clarify '...planned a cephalic birth'. Does this refer to women who initially had a breech presentation which later turned? Is so, consider inserting the words 'after breech turned' after the words 'cephalic birth.', if this is correct. Author Response: We have added ‘after spontaneous version or external cephalic version’ for clarity 2. Methods: Procedures First paragraph- Please insert 'ECV' after 'declined' i.e. '...regarding mode of birth if declined [ECV].' Author Response: We have changed this to ‘if ECV failed or was declined’ for clarity. Outcomes First paragraph - I suggest you insert ‘outcomes including:...’ after ‘short term’ Please insert '1-16' after 'Below each table' Author Response: Changed as suggested. Statistical analysis In paragraph 5, please explain by what means a fetus was 'discovered' to be presenting breech in labour...' i.e. was this by confirmed by scan? Author Response: The word ‘discovered’ is one of the Inclusion criteria from the protocol, so cannot be altered. This discovery may be by ultrasound scan if time permits, but sometimes it is determined solely by vaginal examination or visualisation of the buttocks on the perineum. Paragraph 6, Should PPI be PPIE? Please correct as needed, here and subsequently. Author Response: We have searched for all instances of PPI and replaced with PPIE. Paragraph 6, clause 6), Perhaps rephrase as 'our PPI group was keen to ensure participants were not disadvantaged by nationality, ethnicity or skin colour’? and later consider using the term 'non-Caucasian British' or 'non-Caucasian-non British' in the tables. Was this a unanimous decision or a proportion of the PPI group? How many members were in the PPI group? Reference to skin colour in academic publications is not current practice, though I appreciate your point and Lancet citation with evidence of inequity based on skin colour. If you still intend to refer to colour, you may need to emphasis more why you are doing this, and use footnote for Table 1 to provide the Lancet citation after the first two rows under the heading 'Any other ethnic group'. Author Response: I cannot remember how many people were present when this was discussed, but the specific language used was suggested by a black member of research group, based on diversity reporting guidelines used in the UK. The group were unanimous that we needed to get over our discomfort of referring to skin colour and make it visible. We have added a reference to the Lancet article as suggested in the text. We have also added a further explanatory paragraph in the discussion. 3. Results: The Key Questions that are addressed in each table is a novel and useful way to present the findings. However, the Results section could benefit with a summary of the findings similar to in your abstract, as it otherwise goes straight to the tables which are numerous. Tables Please capitalise the first letter of the first word for all outcomes throughout all tables. Table 1, I suggest you rephrase the heading 'Diagnosis prior to labour', to ‘Timing of diagnosis’, given row 2 under this heading refers to 'in labour...' Author Response: Changed as suggested. Table 3, There should be a separate row for mortality. Author Response: This has been added to all neonatal outcome tables. Please clarify why the legend describing the definition of severe morbidity, does not appear to be reflected in the numbers (%) provided for 'Severe neonatal morbidity/mortality prior to discharge.' - Please make it possible for the reader to see the numbers for the parts that make up this composite outcome. Author Response: This has been added to all neonatal outcome tables. Please check all percentages in all tables. Author Response: These have been checked.

The Discussion refers to relevant studies which align with the design of OptiBreech cohort study, and considerations for the OptiBreech guideline. Paragraph 3, the sentence 'We have therefore reported 200 prospective VBBs across three studies, with one serious adverse neonatal outcomes (0.5%)', is confusing. Please insert 'including the present study' after 'three studies' to improve clarity. (if this is what is meant). Author Response: Changed as suggested. Second to last paragraph, first sentence, please explain what you mean by cultural change? Are you referring to the culture of labour care concerning the umbilical cord or other cultural changes? Author Response: We have changed the word ‘cultural’ to ‘clinical’ for clarity. Thank you for undertaking and continuing this most important work, and your preparatory studies. Thank you for your careful and considered review, and kind words.Congratulations on conducting the OptiBreech collaborative care study and documenting the comprehensive interim analysis that may lead to improved outcomes for women and their babies following breech presentation. I suggest some minor revisions and points to consider below. The manuscript is well written but due to the multi-dimensional cohort, the reader may need extra clarification of these where relevant throughout the text. There appears to be some formatting issues for some words that include unnecessary spaces and dashes. More importantly there appear to be some errors in the tables and need for some data concerning adverse events to be presented in separate rows.Competing Interests: SW and ES are co-Directors of Breech Birth Network, an asset-locked, not-for-profit Community Interest Company that owns the Intellectual Property for the Physiological Breech Birth training materials used in this study. Almost all members of the OptiBreech Collaborative have contributed to teaching on this course and have received modest payments and expenses for doing so. Close Comments 1. Abstract:

It would be helpful to insert '(Table 8)', after first sentence of Results in the Abstract. It would help clarify the results if you insert the text '(all presentations)' after 'achieved a vaginal birth' in line one of Results. Author Response: Referring to a Table in an Abstract is not standard practice, so we have not done this. We feel that (all presentations) would be confusing in the Abstract without the benefit of further explanation. Please correct percentage 2/52 (3.7%) in Results - it should be 3.8%. Author Response: All results have been updated with the remaining data and double-checked. Please clarify '...planned a cephalic birth'. Does this refer to women who initially had a breech presentation which later turned? Is so, consider inserting the words 'after breech turned' after the words 'cephalic birth.', if this is correct. Author Response: We have added ‘after spontaneous version or external cephalic version’ for clarity 2. Methods: Procedures First paragraph- Please insert 'ECV' after 'declined' i.e. '...regarding mode of birth if declined [ECV].' Author Response: We have changed this to ‘if ECV failed or was declined’ for clarity. Outcomes First paragraph - I suggest you insert ‘outcomes including:...’ after ‘short term’ Please insert '1-16' after 'Below each table' Author Response: Changed as suggested. Statistical analysis In paragraph 5, please explain by what means a fetus was 'discovered' to be presenting breech in labour...' i.e. was this by confirmed by scan? Author Response: The word ‘discovered’ is one of the Inclusion criteria from the protocol, so cannot be altered. This discovery may be by ultrasound scan if time permits, but sometimes it is determined solely by vaginal examination or visualisation of the buttocks on the perineum. Paragraph 6, Should PPI be PPIE? Please correct as needed, here and subsequently. Author Response: We have searched for all instances of PPI and replaced with PPIE. Paragraph 6, clause 6), Perhaps rephrase as 'our PPI group was keen to ensure participants were not disadvantaged by nationality, ethnicity or skin colour’? and later consider using the term 'non-Caucasian British' or 'non-Caucasian-non British' in the tables. Was this a unanimous decision or a proportion of the PPI group? How many members were in the PPI group? Reference to skin colour in academic publications is not current practice, though I appreciate your point and Lancet citation with evidence of inequity based on skin colour. If you still intend to refer to colour, you may need to emphasis more why you are doing this, and use footnote for Table 1 to provide the Lancet citation after the first two rows under the heading 'Any other ethnic group'. Author Response: I cannot remember how many people were present when this was discussed, but the specific language used was suggested by a black member of research group, based on diversity reporting guidelines used in the UK. The group were unanimous that we needed to get over our discomfort of referring to skin colour and make it visible. We have added a reference to the Lancet article as suggested in the text. We have also added a further explanatory paragraph in the discussion. 3. Results: The Key Questions that are addressed in each table is a novel and useful way to present the findings. However, the Results section could benefit with a summary of the findings similar to in your abstract, as it otherwise goes straight to the tables which are numerous. Tables Please capitalise the first letter of the first word for all outcomes throughout all tables. Table 1, I suggest you rephrase the heading 'Diagnosis prior to labour', to ‘Timing of diagnosis’, given row 2 under this heading refers to 'in labour...' Author Response: Changed as suggested. Table 3, There should be a separate row for mortality. Author Response: This has been added to all neonatal outcome tables. Please clarify why the legend describing the definition of severe morbidity, does not appear to be reflected in the numbers (%) provided for 'Severe neonatal morbidity/mortality prior to discharge.' - Please make it possible for the reader to see the numbers for the parts that make up this composite outcome. Author Response: This has been added to all neonatal outcome tables. Please check all percentages in all tables. Author Response: These have been checked.

The Discussion refers to relevant studies which align with the design of OptiBreech cohort study, and considerations for the OptiBreech guideline. Paragraph 3, the sentence 'We have therefore reported 200 prospective VBBs across three studies, with one serious adverse neonatal outcomes (0.5%)', is confusing. Please insert 'including the present study' after 'three studies' to improve clarity. (if this is what is meant). Author Response: Changed as suggested. Second to last paragraph, first sentence, please explain what you mean by cultural change? Are you referring to the culture of labour care concerning the umbilical cord or other cultural changes? Author Response: We have changed the word ‘cultural’ to ‘clinical’ for clarity. Thank you for undertaking and continuing this most important work, and your preparatory studies. Thank you for your careful and considered review, and kind words. Views 0 How to cite this report: Morris S. Reviewer Report For: How safe is it to plan a vaginal breech birth with OptiBreech collaborative care?: analysis of cumulative data within the OptiBreech Multiple Trials Cohort [version 2; peer review: 2 approved, 1 approved with reservations]. NIHR Open Res 2025, 3:61 (https://doi.org/10.3310/nihropenres.14650.r30827) The direct URL for this report is: https://openresearch.nihr.ac.uk/articles/3-61/v1#referee-response-30827 https://openresearch.nihr.ac.uk/articles/3-61/v1#referee-response-30827 NOTE: it is important to ensure the information in square brackets after the title is included in this citation. Reviewer Report 20 Dec 2023 Approved VIEWS 0 Thank you for the invitation to review the article titled How safe is it to plan a vaginal breech birth with Optibreech collaborative care?: Analysis of cumulative data within the Optibreech Multiple Trials Cohort. The title ... Continue reading I confirm that I have read this submission and believe that I have an appropriate level of expertise to confirm that it is of an acceptable scientific standard. Close The title ... Continue reading Thank you for the invitation to review the article titled How safe is it to plan a vaginal breech birth with Optibreech collaborative care?: Analysis of cumulative data within the Optibreech Multiple Trials Cohort. The title of the paper provides a clear outline of the scope of the article which is well written and presented appropriately. The methodological processes are clearly documented and easy to follow, allowing for replication. The authors should be commended for the level of consumer involvement in the co-design of the Optibreech research. The authors have provided adequate justification for the chosen methodology with clearly stated objectives and succinctly reported results demonstrating adequate review of the literature. The use of descriptive statistics is appropriate for this data set. Data availability is also outlined within. The authors have made appropriate conclusions while acknowledging the limitations on interpretation of the data at this point in the study. The figures and tables presented are clear and numerous. Having corresponding questions connected to the data tables is helpful. Please note that Table 10 contains an asterisk, but it is not included in the Legend. The authors should be congratulated on their work. I have the following feedback/suggestions/queries: The title of the paper provides a clear outline of the scope of the article which is well written and presented appropriately. The methodological processes are clearly documented and easy to follow, allowing for replication. The authors should be commended for the level of consumer involvement in the co-design of the Optibreech research. The authors have provided adequate justification for the chosen methodology with clearly stated objectives and succinctly reported results demonstrating adequate review of the literature. The use of descriptive statistics is appropriate for this data set. Data availability is also outlined within. The authors have made appropriate conclusions while acknowledging the limitations on interpretation of the data at this point in the study. The figures and tables presented are clear and numerous. Having corresponding questions connected to the data tables is helpful. Please note that Table 10 contains an asterisk, but it is not included in the Legend. The authors should be congratulated on their work. I have the following feedback/suggestions/queries: - I think it would be helpful to separate the data for Category 1 & 2 Caesarean Sections as well as severe morbidity and mortality as there is a significant difference between these categories. - I also think justification is needed for the use of >3cm for being considered active labour when the current literature supports 6cm as established and NHS information sources for consumers reports 4cm as established labour. - Under the Consent Process section, it states that after the “…pilot trial that recruitment focused on women requesting Optibreech care due to a preference for vaginal birth, regardless of fetal position.” Was this fetal position at the time of admission/birth? Does this mean that women with known cephalic presentations were able to request and obtain Optibreech care or did they experience a breech presentation at some point? - Is the work clearly and accurately presented and does it cite the current literature? Yes - Is the study design appropriate and is the work technically sound? Yes - Are sufficient details of methods and analysis provided to allow replication by others? Yes - If applicable, is the statistical analysis and its interpretation appropriate? Yes - Are all the source data underlying the results available to ensure full reproducibility? Yes - Are the conclusions drawn adequately supported by the results? Yes Competing Interests: I have collaborated with Dr Walker in the last 3 years on 2 student projects and was a co-applicant on an NIHR grant application (funding not obtained). My work is also referenced within the article. Reviewer Expertise: Women's experiences of breech diagnosis, care and birth & the recommended care for women with breech pregnancies. CITE HOW TO CITE THIS REPORT Morris S. Reviewer Report For: How safe is it to plan a vaginal breech birth with OptiBreech collaborative care?: analysis of cumulative data within the OptiBreech Multiple Trials Cohort [version 2; peer review: 2 approved, 1 approved with reservations]. NIHR Open Res 2025, 3:61 (https://doi.org/10.3310/nihropenres.14650.r30827) The direct URL for this report is: https://openresearch.nihr.ac.uk/articles/3-61/v1#referee-response-30827 https://openresearch.nihr.ac.uk/articles/3-61/v1#referee-response-30827 NOTE: it is important to ensure the information in square brackets after the title is included in all citations of this article. - Author Response 14 Nov 2025Shawn Walker, Women and Children's Health, King's College London, London, UK14 Nov 2025Author ResponseThank you for the invitation to review the article titled How safe is it to plan a vaginal breech birth with Optibreech collaborative care?: Analysis of cumulative data within the Optibreech ... Continue reading Thank you for the invitation to review the article titled How safe is it to plan a vaginal breech birth with Optibreech collaborative care?: Analysis of cumulative data within the Optibreech Multiple Trials Cohort. Thank you for taking the time to complete such a thorough review, and for your kind words. The title of the paper provides a clear outline of the scope of the article which is well written and presented appropriately. The methodological processes are clearly documented and easy to follow, allowing for replication. The authors should be commended for the level of consumer involvement in the co-design of the Optibreech research. The authors have provided adequate justification for the chosen methodology with clearly stated objectives and succinctly reported results demonstrating adequate review of the literature. The use of descriptive statistics is appropriate for this data set. Data availability is also outlined within. The authors have made appropriate conclusions while acknowledging the limitations on interpretation of the data at this point in the study. The figures and tables presented are clear and numerous. Having corresponding questions connected to the data tables is helpful. Please note that Table 10 contains an asterisk, but it is not included in the Legend. Thank you. This has been removed. The authors should be congratulated on their work. I have the following feedback/suggestions/queries:- I think it would be helpful to separate the data for Category 1 & 2 Caesarean Sections as well as severe morbidity and mortality as there is a significant difference between these categories. Thank you for this suggestion. For this report, we focused on the information women and clinicians felt was most significant: how many of the in-labour caesarean births were performed at full dilation. We will bear this in mind for future reports, but we do not feel given the low numbers of births included in this study, further differentiation would add substantial insight. - I also think justification is needed for the use of >3cm for being considered active labour when the current literature supports 6cm as established and NHS information sources for consumers reports 4cm as established labour. We have now included a justification, which is that we used the same categories as those used in the Term Breech Trial for consistency. All births included in these categories were vaginal births, despite a caesarean birth being initially planned, suggesting that they were indeed in active labour when diagnosed. - Under the Consent Process section, it states that after the “…pilot trial that recruitment focused on women requesting Optibreech care due to a preference for vaginal birth, regardless of fetal position.” Was this fetal position at the time of admission/birth? Does this mean that women with known cephalic presentations were able to request and obtain Optibreech care or did they experience a breech presentation at some point? We have changed this to ‘regardless of whether their baby remained in a breech position’ for clarity.Thank you for the invitation to review the article titled How safe is it to plan a vaginal breech birth with Optibreech collaborative care?: Analysis of cumulative data within the Optibreech Multiple Trials Cohort.Competing Interests: SW and ES are co-Directors of Breech Birth Network, an asset-locked, not-for-profit Community Interest Company that owns the Intellectual Property for the Physiological Breech Birth training materials used in this study. Almost all members of the OptiBreech Collaborative have contributed to teaching on this course and have received modest payments and expenses for doing so. Close Thank you for taking the time to complete such a thorough review, and for your kind words. The title of the paper provides a clear outline of the scope of the article which is well written and presented appropriately. The methodological processes are clearly documented and easy to follow, allowing for replication. The authors should be commended for the level of consumer involvement in the co-design of the Optibreech research. The authors have provided adequate justification for the chosen methodology with clearly stated objectives and succinctly reported results demonstrating adequate review of the literature. The use of descriptive statistics is appropriate for this data set. Data availability is also outlined within. The authors have made appropriate conclusions while acknowledging the limitations on interpretation of the data at this point in the study. The figures and tables presented are clear and numerous. Having corresponding questions connected to the data tables is helpful. Please note that Table 10 contains an asterisk, but it is not included in the Legend. Thank you. This has been removed. The authors should be congratulated on their work. I have the following feedback/suggestions/queries:- I think it would be helpful to separate the data for Category 1 & 2 Caesarean Sections as well as severe morbidity and mortality as there is a significant difference between these categories. Thank you for this suggestion. For this report, we focused on the information women and clinicians felt was most significant: how many of the in-labour caesarean births were performed at full dilation. We will bear this in mind for future reports, but we do not feel given the low numbers of births included in this study, further differentiation would add substantial insight. - I also think justification is needed for the use of >3cm for being considered active labour when the current literature supports 6cm as established and NHS information sources for consumers reports 4cm as established labour. We have now included a justification, which is that we used the same categories as those used in the Term Breech Trial for consistency. All births included in these categories were vaginal births, despite a caesarean birth being initially planned, suggesting that they were indeed in active labour when diagnosed. - Under the Consent Process section, it states that after the “…pilot trial that recruitment focused on women requesting Optibreech care due to a preference for vaginal birth, regardless of fetal position.” Was this fetal position at the time of admission/birth? Does this mean that women with known cephalic presentations were able to request and obtain Optibreech care or did they experience a breech presentation at some point? We have changed this to ‘regardless of whether their baby remained in a breech position’ for clarity. COMMENTS ON THIS REPORT - Author Response 14 Nov 2025Shawn Walker, Women and Children's Health, King's College London, London, UK14 Nov 2025Author ResponseThank you for the invitation to review the article titled How safe is it to plan a vaginal breech birth with Optibreech collaborative care?: Analysis of cumulative data within the Optibreech ... Continue reading Thank you for the invitation to review the article titled How safe is it to plan a vaginal breech birth with Optibreech collaborative care?: Analysis of cumulative data within the Optibreech Multiple Trials Cohort. Thank you for taking the time to complete such a thorough review, and for your kind words. The title of the paper provides a clear outline of the scope of the article which is well written and presented appropriately. The methodological processes are clearly documented and easy to follow, allowing for replication. The authors should be commended for the level of consumer involvement in the co-design of the Optibreech research. The authors have provided adequate justification for the chosen methodology with clearly stated objectives and succinctly reported results demonstrating adequate review of the literature. The use of descriptive statistics is appropriate for this data set. Data availability is also outlined within. The authors have made appropriate conclusions while acknowledging the limitations on interpretation of the data at this point in the study. The figures and tables presented are clear and numerous. Having corresponding questions connected to the data tables is helpful. Please note that Table 10 contains an asterisk, but it is not included in the Legend. Thank you. This has been removed. The authors should be congratulated on their work. I have the following feedback/suggestions/queries:- I think it would be helpful to separate the data for Category 1 & 2 Caesarean Sections as well as severe morbidity and mortality as there is a significant difference between these categories. Thank you for this suggestion. For this report, we focused on the information women and clinicians felt was most significant: how many of the in-labour caesarean births were performed at full dilation. We will bear this in mind for future reports, but we do not feel given the low numbers of births included in this study, further differentiation would add substantial insight. - I also think justification is needed for the use of >3cm for being considered active labour when the current literature supports 6cm as established and NHS information sources for consumers reports 4cm as established labour. We have now included a justification, which is that we used the same categories as those used in the Term Breech Trial for consistency. All births included in these categories were vaginal births, despite a caesarean birth being initially planned, suggesting that they were indeed in active labour when diagnosed. - Under the Consent Process section, it states that after the “…pilot trial that recruitment focused on women requesting Optibreech care due to a preference for vaginal birth, regardless of fetal position.” Was this fetal position at the time of admission/birth? Does this mean that women with known cephalic presentations were able to request and obtain Optibreech care or did they experience a breech presentation at some point? We have changed this to ‘regardless of whether their baby remained in a breech position’ for clarity.Thank you for the invitation to review the article titled How safe is it to plan a vaginal breech birth with Optibreech collaborative care?: Analysis of cumulative data within the Optibreech Multiple Trials Cohort.Competing Interests: SW and ES are co-Directors of Breech Birth Network, an asset-locked, not-for-profit Community Interest Company that owns the Intellectual Property for the Physiological Breech Birth training materials used in this study. Almost all members of the OptiBreech Collaborative have contributed to teaching on this course and have received modest payments and expenses for doing so. Close Thank you for taking the time to complete such a thorough review, and for your kind words. The title of the paper provides a clear outline of the scope of the article which is well written and presented appropriately. The methodological processes are clearly documented and easy to follow, allowing for replication. The authors should be commended for the level of consumer involvement in the co-design of the Optibreech research. The authors have provided adequate justification for the chosen methodology with clearly stated objectives and succinctly reported results demonstrating adequate review of the literature. The use of descriptive statistics is appropriate for this data set. Data availability is also outlined within. The authors have made appropriate conclusions while acknowledging the limitations on interpretation of the data at this point in the study. The figures and tables presented are clear and numerous. Having corresponding questions connected to the data tables is helpful. Please note that Table 10 contains an asterisk, but it is not included in the Legend. Thank you. This has been removed. The authors should be congratulated on their work. I have the following feedback/suggestions/queries:- I think it would be helpful to separate the data for Category 1 & 2 Caesarean Sections as well as severe morbidity and mortality as there is a significant difference between these categories. Thank you for this suggestion. For this report, we focused on the information women and clinicians felt was most significant: how many of the in-labour caesarean births were performed at full dilation. We will bear this in mind for future reports, but we do not feel given the low numbers of births included in this study, further differentiation would add substantial insight. - I also think justification is needed for the use of >3cm for being considered active labour when the current literature supports 6cm as established and NHS information sources for consumers reports 4cm as established labour. We have now included a justification, which is that we used the same categories as those used in the Term Breech Trial for consistency. All births included in these categories were vaginal births, despite a caesarean birth being initially planned, suggesting that they were indeed in active labour when diagnosed. - Under the Consent Process section, it states that after the “…pilot trial that recruitment focused on women requesting Optibreech care due to a preference for vaginal birth, regardless of fetal position.” Was this fetal position at the time of admission/birth? Does this mean that women with known cephalic presentations were able to request and obtain Optibreech care or did they experience a breech presentation at some point? We have changed this to ‘regardless of whether their baby remained in a breech position’ for clarity. Alongside their report, reviewers assign a status to the article: - Approved - Approved with reservations - Not approved | Invited Reviewers | ||| |---|---|---|---| | 1 | 2 | 3 | | | Version 2 (revision) 14 Nov 25 | read | || | Version 1 23 Nov 23 | read | read | read | Sign up for content alerts You are now signed up to receive this alert Alongside their report, reviewers assign a status to the article: Approved - the paper is scientifically sound in its current form and only minor, if any, improvements are suggested Approved with reservations - A number of small changes, sometimes more significant revisions are required to address specific details and improve the papers academic merit. Not approved - fundamental flaws in the paper seriously undermine the findings and conclusions Provide sufficient details of any financial or non-financial competing interests to enable users to assess whether your comments might lead a reasonable person to question your impartiality. Consider the following examples, but note that this is not an exhaustive list: Examples of 'Non-Financial Competing Interests' - Within the past 4 years, you have held joint grants, published or collaborated with any of the authors of the selected paper. - You have a close personal relationship (e.g. parent, spouse, sibling, or domestic partner) with any of the authors. - You are a close professional associate of any of the authors (e.g. scientific mentor, recent student). - You work at the same institute as any of the authors. - You hope/expect to benefit (e.g. favour or employment) as a result of your submission. - You are an Editor for the journal in which the article is published. Examples of 'Financial Competing Interests' - You expect to receive, or in the past 4 years have received, any of the following from any commercial organisation that may gain financially from your submission: a salary, fees, funding, reimbursements. - You expect to receive, or in the past 4 years have received, shared grant support or other funding with any of the authors. - You hold, or are currently applying for, any patents or significant stocks/shares relating to the subject matter of the paper you are commenting on. Sign up for content alerts and receive a weekly or monthly email with all newly published articles Register with NIHR Open Research Already registered? Sign in close Error If you are a previous or current NIHR award holder, sign up for information about developments, publishing and publications from NIHR Open Research. We'll keep you updated on any major new updates to NIHR Open Research Sign In If you've forgotten your password, please enter your email address below and we'll send you instructions on how to reset your password. Email us for further assistance. The email address should be the one you originally registered with F1000. Email address not valid, please try again You registered with F1000 via Google, so we cannot reset your password. To sign in, please click here. If you still need help with your Google account password, please click here. You registered with F1000 via Facebook, so we cannot reset your password. To sign in, please click here. If you still need help with your Facebook account password, please click here. Code not correct, please try again Server error, please try again. If your email address is registered with us, we will email you instructions to reset your password. If you think you should have received this email but it has not arrived, please check your spam filters and/or contact for further assistance. Please wait...