Thank you for inviting us to respond to the commentary, “Upright Breech Birth: New Video Research Risks Reviving Friedman's Curse.”

Although others have been observing breech mechanisms and videos for some time,1, 2 we were the first to undertake and report with data the results of a systematic study.3 We welcome our findings to be refined or altered, with larger samples and ideally with prospectively collected videos.

As the commentators rightly point out, the algorithm was presented as an initial framework to guide teaching, research, and practice,3 with the only available evidence about the timings of emergence. Although the Louwen et al4 study presented a protocol description in a Supplementary Appendix, there was no Frankfurt algorithm—if there were, Dr Reitter, as the last author on the paper, would have known about it and cited it appropriately. Although avoiding a focus on timings is strongly advocated for by the commentators, our preferred strategy has been to support less-experienced clinicians to maintain situational awareness, to avoid death or damage by including timing as one of many considerations. We aim to provide clear parameters for normality—based on the current state of the science, yet knowing these will continue to be refined in ongoing research—so that clinicians understand when help is likely to be needed—and when it is not.

We propose that a more productive way to work through these differences in approach is through continued research based on them. We have carried out a case-control study, led by Consultant Midwife Emma Spillane, using a prespecified sample in a large teaching hospital unaffiliated with any of our authors during the sample period (in peer review).5 The results confirmed an association between exceeding the time frames in the algorithm and neonatal admission or death (cases). We have also continued to work closely with the OptiBreech patient and public involvement (PPI) group to identify the outcomes important to women, birthing people, and their partners.6 Women have told us they want more than a birth with no long-term sequelae. Ideally, they want no separation from their baby, neither immediately (eg, cord clamping and resuscitation) nor short-term (eg, neonatal admission). Our work is increasingly focused on achieving a balance between enough intervention to achieve these goals, while avoiding unnecessary iatrogenic harm.

The commentators express concerns that presenting a framework for what is “normal” for breech births may escalate alarm among fearful practitioners or prompt unnecessary episiotomies and forceps. The possibility that research will be misapplied, in our opinions, is not a reason to not publish it. In addition, these hypotheses can be tested through evaluation of training based on the algorithm, which we have done and published in this journal.7 Our evaluation involved midwives and doctors working in eight United Kingdom National Health Service (NHS) hospitals. Teaching based on the algorithm, including some guidelines around timing, resulted in a significant increase in confidence to manage a vaginal breech birth and a nonsignificant increase in vaginal breech birth rates in all but one of the participating hospitals.7 Among births attended by those who completed training, episiotomy rates were 5% (1/21) and intact perinea were 52% (11/21)—better outcomes than one would expect in a similar sample of cephalic births.

The commentators also express concern that we refer to the maneuver we use regularly as “shoulder press” rather than “Frank's Nudge,” AND that we describe doing it differently from Dr Louwen originally described “his maneuver.” We feel that it is important to describe exactly what we are doing so that we can observe effectiveness and complication rates associated with these variations. In addition if what we are doing is different from what Dr Louwen described, we should not put his name to it. We feel similarly about our use of the descriptive term “scoop and flex.” The category of various maneuvers we are observing and describing, as Ms Daviss seems to agree, is different from what she has described as “the crowning touch,” so we do not attribute it to that source nor did those who described them to us or have written about it.8

Although we have the utmost respect for Dr Louwen and Ms Daviss, there is rarely one “correct” way of doing any maneuver that works for every baby and every mother every time. Rather, the ability to vary maneuvers slightly to meet the needs of a unique, unfolding situation is a marker of experience for breech attendants.9 However, until this experience develops, we feel that clear guidance about when and how to intervene is helpful.

Our experience of teaching breech skills over many years also indicates that concepts, rather than eponyms, are easier to learn and remember.7, 8, 10, 11 Dr Walker was first introduced to the breech mechanisms and variations of them as indications for specific interventions in 2010, when she began learning from and teaching with United Kingdom midwives Mary Cronk12 and Jane Evans.2, 13 We honor and reference both of these inspiring women frequently, though our own observations have not always led us to the same conclusions. Dr Walker's first encounters with published descriptions of UVBB theory and practice were through Dr Maggie Banks’ Breech Birth Woman-Wise, Cronk and Evans’ articles, and their joint work published in Anne Frye's Holistic Midwifery.14 She first wrote about using the maneuvers she learned from them and through her own practice, including shoulder press, in 2014 by means of blog15 and 2015 by means of print16; there would have been no way to attribute this to a description that had not yet been published.4

Since 2012, we have worked closely with each other and others to refine our understandings and the algorithm. Between us, we have directly implemented UVBB after the algorithm in multiple hospitals in the United Kingdom and Germany,17, 18 where vaginal breech birth services have been defunct for years, and supported the implementation in others throughout Europe.19, 20 We believe this does constitute over a decade of “actual experience, evidence, and expertise.”

Finally, we believe, as did Thomas Kuhn, that the structure of scientific revolutions is one of the gradual paradigm shifts.21 In maternity care, we never work in isolation. Nothing gets to publication without being inspired by, discussed with, and influenced by our colleagues and collaborators. Our insights and observations always build on the work of others, gradually adding new pieces to the puzzle, usually only a small piece at a time. The commentators are absolutely correct that a paper such as the video study is not and cannot be interpreted as an absolute truth, after which rigid restrictions should be imposed. But it shines a light on a new area of our common practice, which we now appear to be focusing on with debates from our varied perspectives. This can only be a good thing.