Shawn Walker
Current Organizations / Institutes
The organizations/institutes from the scholar's latest article
Previous Organizations / Institutes
The organizations / institutes from the scholar's other articles in the past ten years
Research Subjects
Research Interests
Shawn Walker has a total of 90 co-authors. Here are the top co-authors by number of shared publications:
- Emma Spillane
Maternity Services, Kingston NHS Foundation Trust, Kingston upon Thames, London, KT2 7QB, UK
5 shared publications - Tisha Dasgupta
Department of Women & Children’s Health, School of Life Course and Population Sciences, King’s College London, United Kingdom
5 shared publications Andrew Shennan
Kings College London
4 shared publicationsJane Sandall
King's College London Faculty of Life Sciences and Medicine
4 shared publicationsTisha Dasgupta
Department of women & children's health, King's College London, London, United Kingdom
4 shared publications- Andrew H. Shennan
Department of Women and Children's Health St Thomas' Hospital, King's College London London UK
3 shared publications
Latest Publications
- 14 August 2026
- Published by Taylor & Francis
- p. 187-195
Facilitating Physiological Breech Birth
Approximately 5% of term pregnancies present in breech. Reduced exposure to vaginal breech birth by clinicians has narrowed the choice and contributed to avoidable harm. Emerging evidence supports physiological vaginal breech birth and structured management using the Physiological Breech Birth Algorithm. The OptiBreech Collaborative Care model operationalises this evidence through specialist clinics, continuity of care, and trained teams. Evidence demonstrates improved informed choice, neonatal outcomes comparable or superior to standard care, and cost-effectiveness. Core safety principles include timely progress once the buttocks are visible, completion of birth within 7 minutes, sustained maternal effort, and intact–cord resuscitation when needed.
- 14 August 2026
- Published by Taylor & Francis
- p. 187-195
Facilitating Physiological Breech Birth
Approximately 5% of term pregnancies present in breech. Reduced exposure to vaginal breech birth by clinicians has narrowed the choice and contributed to avoidable harm. Emerging evidence supports physiological vaginal breech birth and structured management using the Physiological Breech Birth Algorithm. The OptiBreech Collaborative Care model operationalises this evidence through specialist clinics, continuity of care, and trained teams. Evidence demonstrates improved informed choice, neonatal outcomes comparable or superior to standard care, and cost-effectiveness. Core safety principles include timely progress once the buttocks are visible, completion of birth within 7 minutes, sustained maternal effort, and intact–cord resuscitation when needed.
- Open Access
- 8 July 2026
- Published by Wiley in Acta Obstetricia et Gynecologica Scandinavica
- Vol. 105 (9) , 1646-1661
Transmasculine pregnancy—Occurrence, associations, and outcomes: A quantitative systematic review
Introduction: Transmasculine people experience incongruence between their gender identity and sex (registered female at birth, AFAB). Little is known about transmasculine pregnancy. This project systematically reviews all published quantitative evidence on transmasculine pregnancy occurrence, associations, and outcomes, using midwifery, obstetric, and transgender health expertise. Material and Methods: Prospero protocol CRD 42020159034. Searches combined concepts of “transmasculine,” registered/assigned female at birth (AFAB), and “pregnancy,” using broad, inclusive sets of MeSH terms and keywords. Database searches: Embase, Maternity and Infant Care and Medline (OVID platform), and CINAHL (EBSCO platform) were searched from 2000 to August 2024, with no language restrictions. Included study references and relevant systematic reviews were also searched. Results: From 2166 citations, 44 studies were included, many of which were small and uncontrolled. Primary outcome: The mean proportion of transmasculine people ever having been pregnant (gravidity) was 5.6%–8.5% (47/835–321/3777, range 0%–16.3%), and the mean proportion having had births (parity) was 4.3%–8.5% (35/806–24/284, range 0%–19.1%). Secondary outcomes: The conception rates during testosterone use were low, but insufficient to rely upon as contraception; miscarriage rates appeared high (4/5 studies had rates between 31.6 and 40%—16/40 per person, 156/493 per pregnancy). Similarly, postnatal depression rates (two studies) range 15–58% (3/20–7/12). The limited data available suggested that testosterone use before pregnancy seemed to be associated with fewer conceptions compared to never having taken it, even where transmasculine people had stopped for several months before attempting conception. Pregnancy loss seemed to be higher in those exposed to testosterone antenatally. There was no or inadequate data on most other important outcomes, including access to care, assisted reproduction, stillbirths, and obstetric and neonatal complications. Conclusions: A significant minority of transmasculine people become pregnant, including after transition. The miscarriage findings warrant further investigation. Reproductive and maternity services should adapt, although minimal information risks negative consequences for users and providers, potentially adding to the lack of trust. Better data collection and research are urgently required in order to provide effective services.
- 8 July 2026
- Published by Wiley in Acta Obstetricia et Gynecologica Scandinavica
- Vol. 105 (9) , 1646-1661
Open AccessTransmasculine pregnancy—Occurrence, associations, and outcomes: A quantitative systematic review
Introduction: Transmasculine people experience incongruence between their gender identity and sex (registered female at birth, AFAB). Little is known about transmasculine pregnancy. This project systematically reviews all published quantitative evidence on transmasculine pregnancy occurrence, associations, and outcomes, using midwifery, obstetric, and transgender health expertise. Material and Methods: Prospero protocol CRD 42020159034. Searches combined concepts of “transmasculine,” registered/assigned female at birth (AFAB), and “pregnancy,” using broad, inclusive sets of MeSH terms and keywords. Database searches: Embase, Maternity and Infant Care and Medline (OVID platform), and CINAHL (EBSCO platform) were searched from 2000 to August 2024, with no language restrictions. Included study references and relevant systematic reviews were also searched. Results: From 2166 citations, 44 studies were included, many of which were small and uncontrolled. Primary outcome: The mean proportion of transmasculine people ever having been pregnant (gravidity) was 5.6%–8.5% (47/835–321/3777, range 0%–16.3%), and the mean proportion having had births (parity) was 4.3%–8.5% (35/806–24/284, range 0%–19.1%). Secondary outcomes: The conception rates during testosterone use were low, but insufficient to rely upon as contraception; miscarriage rates appeared high (4/5 studies had rates between 31.6 and 40%—16/40 per person, 156/493 per pregnancy). Similarly, postnatal depression rates (two studies) range 15–58% (3/20–7/12). The limited data available suggested that testosterone use before pregnancy seemed to be associated with fewer conceptions compared to never having taken it, even where transmasculine people had stopped for several months before attempting conception. Pregnancy loss seemed to be higher in those exposed to testosterone antenatally. There was no or inadequate data on most other important outcomes, including access to care, assisted reproduction, stillbirths, and obstetric and neonatal complications. Conclusions: A significant minority of transmasculine people become pregnant, including after transition. The miscarriage findings warrant further investigation. Reproductive and maternity services should adapt, although minimal information risks negative consequences for users and providers, potentially adding to the lack of trust. Better data collection and research are urgently required in order to provide effective services.
- 1 May 2025
- Published by Wiley in Journal of Midwifery & Women's Health
- Vol. 70 (3) , 422-430
Biodynamic Interventions in Labor: A State of the Science Review
Biodynamic interventions are targeted suggestions for postural changes thought to quicken the progress or ease the discomfort of labor and birth, especially when fetuses are not in the optimal position. Although biodynamic interventions carry almost no risks and come from a rich anecdotal body of evidence, they have generally not been subject to rigorous evaluation. Current clinical practice guidelines support the use of intravenous oxytocin and manual or instrumental rotation for delayed labor progress and fetal malposition; however, these interventions are associated with increased risks of maternal and neonatal morbidities. The use of biodynamic interventions may be an effective alternative to optimizing fetal position and labor progress, with fewer associated risks. This state of the science review examines research describing the efficacy of various biodynamic interventions on labor progress, fetal malposition, and mode of birth within specific clinical contexts. The review also seeks to draw out key findings for clinical practice and identify gaps in the literature for future research.
- 1 May 2025
- Published by Wiley in Journal of Midwifery & Women's Health
- Vol. 70 (3) , 422-430
Biodynamic Interventions in Labor: A State of the Science Review
Biodynamic interventions are targeted suggestions for postural changes thought to quicken the progress or ease the discomfort of labor and birth, especially when fetuses are not in the optimal position. Although biodynamic interventions carry almost no risks and come from a rich anecdotal body of evidence, they have generally not been subject to rigorous evaluation. Current clinical practice guidelines support the use of intravenous oxytocin and manual or instrumental rotation for delayed labor progress and fetal malposition; however, these interventions are associated with increased risks of maternal and neonatal morbidities. The use of biodynamic interventions may be an effective alternative to optimizing fetal position and labor progress, with fewer associated risks. This state of the science review examines research describing the efficacy of various biodynamic interventions on labor progress, fetal malposition, and mode of birth within specific clinical contexts. The review also seeks to draw out key findings for clinical practice and identify gaps in the literature for future research.
- Open Access
- 1 February 2025
- Published by Wiley in Journal of Midwifery & Women's Health
- Vol. 70 (2) , 270-278
The OptiBreech Trial Feasibility Study: A Qualitative Inventory of the Roles and Responsibilities of Breech Specialist Midwives
Background: The safety of vaginal breech birth is associated with the skill and experience of professionals in attendance, but minimal training opportunities exist. OptiBreech collaborative care is an evidence‐based care bundle, based on previous research. This care pathway is designed to improve access to care and the safety of vaginal breech births, when they occur, through dedicated breech clinics and intrapartum support. This improved process also enhances professional training. Care coordination is accomplished in most cases by a key breech specialist midwife on the team. The goal of this qualitative inventory was to describe the roles and tasks undertaken by specialist midwives in the OptiBreech care implementation feasibility study.Methods: Semistructured interviews were conducted with OptiBreech team members (17 midwives and 4 obstetricians; N = 21), via video conferencing software. Template analysis was used to code, analyze, and interpret data relating to the roles of the midwives delivering breech services. Tasks identified through initial coding were organized into 5 key themes in a template, following reflective discussion at weekly staff meetings and stakeholder events. This template was then applied to all interviews to structure the analysis.Results: Breech specialist midwives functioned as change agents. In each setting, they fulfilled similar roles to support their teams, whether this role was formally recognized or not. We report an inventory of tasks performed by breech specialist midwives, organized into 5 themes: care coordination and planning, service development, clinical care delivery, education and training, and research.Discussion: Breech specialist midwives perform a consistent set of roles and responsibilities to co‐ordinate care throughout the OptiBreech pathway. The inventory has been formally incorporated into the OptiBreech collaborative care logic model. This detailed description can be used by employers and professional organizations who wish to formalize similar roles to meet consistent standards and improve care.
- 1 February 2025
- Published by Wiley in Journal of Midwifery & Women's Health
- Vol. 70 (2) , 270-278
Open AccessThe OptiBreech Trial Feasibility Study: A Qualitative Inventory of the Roles and Responsibilities of Breech Specialist Midwives
Background: The safety of vaginal breech birth is associated with the skill and experience of professionals in attendance, but minimal training opportunities exist. OptiBreech collaborative care is an evidence‐based care bundle, based on previous research. This care pathway is designed to improve access to care and the safety of vaginal breech births, when they occur, through dedicated breech clinics and intrapartum support. This improved process also enhances professional training. Care coordination is accomplished in most cases by a key breech specialist midwife on the team. The goal of this qualitative inventory was to describe the roles and tasks undertaken by specialist midwives in the OptiBreech care implementation feasibility study.Methods: Semistructured interviews were conducted with OptiBreech team members (17 midwives and 4 obstetricians; N = 21), via video conferencing software. Template analysis was used to code, analyze, and interpret data relating to the roles of the midwives delivering breech services. Tasks identified through initial coding were organized into 5 key themes in a template, following reflective discussion at weekly staff meetings and stakeholder events. This template was then applied to all interviews to structure the analysis.Results: Breech specialist midwives functioned as change agents. In each setting, they fulfilled similar roles to support their teams, whether this role was formally recognized or not. We report an inventory of tasks performed by breech specialist midwives, organized into 5 themes: care coordination and planning, service development, clinical care delivery, education and training, and research.Discussion: Breech specialist midwives perform a consistent set of roles and responsibilities to co‐ordinate care throughout the OptiBreech pathway. The inventory has been formally incorporated into the OptiBreech collaborative care logic model. This detailed description can be used by employers and professional organizations who wish to formalize similar roles to meet consistent standards and improve care.
- 16 July 2024
- Published by Elsevier in Women and Birth
- Vol. 37 (5) , 101656
Barriers and facilitators for implementation of OptiBreech collaborative care: A qualitative study as part of an implementation process evaluation
- 16 July 2024
- Published by Elsevier in Women and Birth
- Vol. 37 (5) , 101656
Barriers and facilitators for implementation of OptiBreech collaborative care: A qualitative study as part of an implementation process evaluation
- Open Access
- 28 June 2024
- Published by Poltekkes Kemenkes Surabaya in International Journal of Advanced Health Science and Technology
- Vol. 4 (3)
Social Psychological and Cultural Resilience in Its Influence on Exclusive Breastfeeding Behavior
Mother's milk (ASI) is the best food for babies that cannot be replaced by anything. Breastfeeding has been proven to be beneficial for both the baby and the mother. However, the coverage rate for achieving exclusive breastfeeding is still far below the target. This research aims to determine the influence of social psychological and socio-cultural resilience on exclusive breastfeeding behavior. This research is an analytical study with a cross sectional design. The sample in this study was 108 postpartum mothers taken using a simple random sampling technique. The independent variables in this research are social psychological and socio-cultural resilience, while the dependent variable is the behavior of postpartum mothers in providing exclusive breastfeeding. Data collection in this study used a questionnaire and was analyzed bivariately using the Chi Square and Fisher Exact Tests, while multivariate analysis used the Logistic Regression Test. The results of analysis using the Chi Square and/or Fisher Exact tests showed a p value > 0.05 for all indicators of social psychological resilience, which means that there are no indicators in this dimension that have an influence on exclusive breastfeeding. Meanwhile, for the socio-cultural resilience variable, the result was a p value of 0.014 or p value <0.05 on the social care indicator, which means that social care has a significant influence on exclusive breastfeeding. So it can be concluded that social psychological resilience has no effect on exclusive breastfeeding, while socio-cultural resilience influences exclusive breastfeeding on indicators of social concern.
- 28 June 2024
- Published by Poltekkes Kemenkes Surabaya in International Journal of Advanced Health Science and Technology
- Vol. 4 (3)
Open AccessSocial Psychological and Cultural Resilience in Its Influence on Exclusive Breastfeeding Behavior
Mother's milk (ASI) is the best food for babies that cannot be replaced by anything. Breastfeeding has been proven to be beneficial for both the baby and the mother. However, the coverage rate for achieving exclusive breastfeeding is still far below the target. This research aims to determine the influence of social psychological and socio-cultural resilience on exclusive breastfeeding behavior. This research is an analytical study with a cross sectional design. The sample in this study was 108 postpartum mothers taken using a simple random sampling technique. The independent variables in this research are social psychological and socio-cultural resilience, while the dependent variable is the behavior of postpartum mothers in providing exclusive breastfeeding. Data collection in this study used a questionnaire and was analyzed bivariately using the Chi Square and Fisher Exact Tests, while multivariate analysis used the Logistic Regression Test. The results of analysis using the Chi Square and/or Fisher Exact tests showed a p value > 0.05 for all indicators of social psychological resilience, which means that there are no indicators in this dimension that have an influence on exclusive breastfeeding. Meanwhile, for the socio-cultural resilience variable, the result was a p value of 0.014 or p value <0.05 on the social care indicator, which means that social care has a significant influence on exclusive breastfeeding. So it can be concluded that social psychological resilience has no effect on exclusive breastfeeding, while socio-cultural resilience influences exclusive breastfeeding on indicators of social concern.
- Open Access
- 1 June 2024
- Published by Elsevier in European Journal of Obstetrics & Gynecology and Reproductive Biology
- Vol. 299, 78-82
Variations of cervical head entrapment in vaginal breech births: New insights on how to prevent, manage and resolve
- 1 June 2024
- Published by Elsevier in European Journal of Obstetrics & Gynecology and Reproductive Biology
- Vol. 299, 78-82
Open AccessVariations of cervical head entrapment in vaginal breech births: New insights on how to prevent, manage and resolve
- Open Access
- 31 January 2024
- Published by Wiley
Breech Specialist Midwives in the OptiBreech Trial feasibility study: an implementation process evaluation
Objective: Refine the programme theory for OptiBreech Care Design: Concurrent mixed methods implementation process evaluation Setting: 6 NHS hospitals in England participating in the OptiBreech 1 Feasibility Study Sample: 15 women planning a vaginal breech birth at term and 6 breech lead midwives Methods: Outcomes were recorded on case report forms and descriptively analysed. Interviews were recorded, transcribed and analysed using the Theoretical Framework of Acceptability. Iterative analysis informed subsequent interviews and the on-going process of implementation across sites. Main Outcome Measures: Acceptability of service delivery models and their outcomes. Results: Actively recruiting Trusts implemented services through a dedicated clinic and/or a proficient intrapartum support service, organised and provided primarily by a Breech Specialist Midwife. While we identified challenges, this model has achieved 93% fidelity to the intervention’s goal of ensuring attendance of OptiBreech-trained professionals at vaginal breech births, and it is highly acceptable to women. Our initial suggested model of a multi-disciplinary team composed of 5 obstetricians and 5 midwives does not appear feasible, due to very low overall current breech experience levels and the context of current pressures on NHS services. Conclusions: Appointment of a Breech Specialist Midwife, whose role is to co-ordinate a dedicated clinic, training and a proficient intrapartum care team, appears to be highly acceptable to women. This model appears to be a feasible implementation strategy, in order to test the safety and effectiveness of OptiBreech Care in a clinical trial, but further work needs to be done to develop sustainability.
- 31 January 2024
- Published by Wiley
Open AccessBreech Specialist Midwives in the OptiBreech Trial feasibility study: an implementation process evaluation
Objective: Refine the programme theory for OptiBreech Care Design: Concurrent mixed methods implementation process evaluation Setting: 6 NHS hospitals in England participating in the OptiBreech 1 Feasibility Study Sample: 15 women planning a vaginal breech birth at term and 6 breech lead midwives Methods: Outcomes were recorded on case report forms and descriptively analysed. Interviews were recorded, transcribed and analysed using the Theoretical Framework of Acceptability. Iterative analysis informed subsequent interviews and the on-going process of implementation across sites. Main Outcome Measures: Acceptability of service delivery models and their outcomes. Results: Actively recruiting Trusts implemented services through a dedicated clinic and/or a proficient intrapartum support service, organised and provided primarily by a Breech Specialist Midwife. While we identified challenges, this model has achieved 93% fidelity to the intervention’s goal of ensuring attendance of OptiBreech-trained professionals at vaginal breech births, and it is highly acceptable to women. Our initial suggested model of a multi-disciplinary team composed of 5 obstetricians and 5 midwives does not appear feasible, due to very low overall current breech experience levels and the context of current pressures on NHS services. Conclusions: Appointment of a Breech Specialist Midwife, whose role is to co-ordinate a dedicated clinic, training and a proficient intrapartum care team, appears to be highly acceptable to women. This model appears to be a feasible implementation strategy, in order to test the safety and effectiveness of OptiBreech Care in a clinical trial, but further work needs to be done to develop sustainability.
- Open Access
- 15 November 2023
- Published by Public Library of Science (PLoS) in PLOS ONE
- Vol. 18 (11) , e0294139
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 randomised trial nested within a cohort
OptiBreech collaborative care is a multi-disciplinary care pathway for breech presentation at term, with continuity from a breech specialist midwife, including where chosen, for vaginal breech birth (VBB). Pilot randomised trial using unblinded 1:1 parallel group allocation to OptiBreech versus standard care, within a cohort. Participants were women with a breech-presenting fetus > 33 weeks, at four sites in England, January–June 2022. A two-stage consent process was used. Participants consented to undergo random selection to be offered a ‘new care process’, with a choice to accept it, or not. Primary objectives were to identify recruitment, acceptance, and attrition rates. Randomisation procedures and potential primary outcomes for a substantive study were also feasibility-tested. 68 women were randomised between January–June 2022. The consent process was acceptable to participants, but randomisation was unacceptable to women who specifically sought OptiBreech care. Two women withdrew due to concerns about sharing personal information. More women planned a VBB when randomised to OptiBreech Care (23.5% vs 0, p = .002, 95% CI = 9.3%,37.8%). Women randomised to OptiBreech care had: lower rates of cephalic presentation at birth (38.2% vs 54.5%), higher rates of vaginal birth (32.4% vs 24.2%), lower rates of in-labour caesarean birth (20.6% vs 36.4%), lower rates of neonatal intensive care (5.9% vs 9.1%), and lower rates of severe neonatal morbidity (2.9% vs 9.1%). Randomisation was stopped on the advice of the steering committee before the planned sample of 104, as lack of access to VBB within standard care prohibited comparison of outcomes. Demand for VBB is sufficient for a cohort study, but comparison of outcomes by 1:1 randomisation is not feasible. OptiBreech care would be best evaluated using stepped wedge cluster randomisation. Funded by the United Kingdom National Institute for Health and Care Research (NIHR300582). Clinical trial registration: ISRCTN 14521381.
- 15 November 2023
- Published by Public Library of Science (PLoS) in PLOS ONE
- Vol. 18 (11) , e0294139
Open AccessOptiBreech 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 randomised trial nested within a cohort
OptiBreech collaborative care is a multi-disciplinary care pathway for breech presentation at term, with continuity from a breech specialist midwife, including where chosen, for vaginal breech birth (VBB). Pilot randomised trial using unblinded 1:1 parallel group allocation to OptiBreech versus standard care, within a cohort. Participants were women with a breech-presenting fetus > 33 weeks, at four sites in England, January–June 2022. A two-stage consent process was used. Participants consented to undergo random selection to be offered a ‘new care process’, with a choice to accept it, or not. Primary objectives were to identify recruitment, acceptance, and attrition rates. Randomisation procedures and potential primary outcomes for a substantive study were also feasibility-tested. 68 women were randomised between January–June 2022. The consent process was acceptable to participants, but randomisation was unacceptable to women who specifically sought OptiBreech care. Two women withdrew due to concerns about sharing personal information. More women planned a VBB when randomised to OptiBreech Care (23.5% vs 0, p = .002, 95% CI = 9.3%,37.8%). Women randomised to OptiBreech care had: lower rates of cephalic presentation at birth (38.2% vs 54.5%), higher rates of vaginal birth (32.4% vs 24.2%), lower rates of in-labour caesarean birth (20.6% vs 36.4%), lower rates of neonatal intensive care (5.9% vs 9.1%), and lower rates of severe neonatal morbidity (2.9% vs 9.1%). Randomisation was stopped on the advice of the steering committee before the planned sample of 104, as lack of access to VBB within standard care prohibited comparison of outcomes. Demand for VBB is sufficient for a cohort study, but comparison of outcomes by 1:1 randomisation is not feasible. OptiBreech care would be best evaluated using stepped wedge cluster randomisation. Funded by the United Kingdom National Institute for Health and Care Research (NIHR300582). Clinical trial registration: ISRCTN 14521381.