Background: Smoking during pregnancy increases the risk of multiple serious adverse infant, child and maternal outcomes, yet nearly 10% of Australian women still smoke during pregnancy. Despite evidence-based guidelines that recommend routine and repeated smoking cessation support (SCS) for all pregnant women, the provision of recommended SCS remains poor. Guidance on developing complex interventions to improve health care recommends drawing on existing theories, reviewing evidence, undertaking primary data collection, attending to future real-world implementation and designing and refining interventions using iterative cycles with stakeholder input throughout. Here, we describe using the Behaviour Change Wheel (BCW) and the Theoretical Domains Framework to apply these principles in developing an intervention to improve the provision of SCS in Australian maternity services. Methods: Working closely with key stakeholders in the New South Wales (NSW) health system, we applied the steps of the BCW method then undertook a small feasibility study in one service to further refine the intervention. Stakeholders were engaged in multiple ways—as a core research team member, through a project Advisory Group, targeted meetings with policymakers, a large workshop to review potential components and the feasibility study. Results: Barriers to and enablers of providing SCS were identified in five of six components described in the BCW method (psychological capability, physical opportunity, social opportunity and reflective and automatic motivation). These were mapped to intervention types and we selected education, training, enablement, environmental restructuring, persuasion, incentivisation and modelling as suitable in our context. Through application of the APEASE criteria (Affordability, Practicability, Effectiveness, Acceptability, Side effects and Equity) in the stakeholder workshop, behaviour change techniques were selected and applied in developing the intervention which includes systems, clinician and leadership elements. The feasibility study confirmed the feasibility and acceptability of the midwifery component and the need to further strengthen the leadership component. Conclusions: Using the BCW method combined with strong stakeholder engagement from inception resulted in transparent development of the MOHMQuit intervention, which targets identified barriers to and enablers of the provision of SCS and is developed specifically for the context in which it will be implemented. The intervention is being trialled in eight public maternity services in NSW.

Background: Smoking is the most important preventable cause of adverse pregnancy outcomes, but provision of smoking cessation support (SCS) to pregnant women is poor. We examined the association between midwives’ implementation of SCS (5As – Ask, Advise, Assess, Assist, Arrange follow-up) and reported barriers/enablers to implementation.Methods: On-line anonymous survey of midwives providing antenatal care in New South Wales (NSW), Australia, assessing provision of the 5As and barriers/enablers to their implementation, using the Theoretical Domains Framework (TDF). Factor analyses identified constructs underlying the 5As; and barriers/enablers. Multivariate general linear models examined relationships between the barrier/enabler factors and the 5As factors.Results: Of 750 midwives invited, 150 (20%) participated. Respondents more commonly reported Asking and Assessing than Advising, Assisting, or Arranging follow-up (e.g. 77% always Ask smoking status; 17% always Arrange follow-up). Three 5As factors were identified– ‘Helping’, ‘Assessing quitting’ and ‘Assessing dependence’. Responses to barrier/enabler items showed greater knowledge, skills, intentions, and confidence with Assessment than Assisting; endorsement for SCS as a priority and part of midwives’ professional role; and gaps in training and organisational support for SCS. Nine barrier/enabler factors were identified. Of these, the factors of ‘Capability’(knowledge, skills, confidence); ‘Work Environment’ (service has resources, capacity, champions and values SCS) and ‘Personal priority’ (part of role and a priority) predicted ‘Helping’.Conclusion: The TDF enabled systematic identification of barriers to providing SCS, and the multivariate models identified key contributors to poor implementation. Combined with qualitative data, these results have been mapped to intervention components to develop a comprehensive intervention to improve SCS.

Background: Smoking during pregnancy is the most important preventable cause of adverse pregnancy outcomes, yet smoking cessation support (SCS) is inconsistently provided. The MOMHQUIT intervention was developed to address this evidence-practice gap, using the Behaviour Change Wheel method by mapping barriers to intervention strategies. MOHMQuit includes systems, leadership and clinician elements. This implementation trial will determine the effectiveness and cost-effectiveness of MOHMQuit in improving smoking cessation rates in pregnant women in public maternity care services in Australia; test the mechanisms of action of the intervention strategies; and examine implementation outcomes. Methods: A stepped-wedge cluster-randomised design will be used. Implementation of MOHMQuit will include reinforcing leadership investment in SCS as a clinical priority, strengthening maternity care clinicians’ knowledge, skills, confidence and attitudes towards the provision of SCS, and clinicians’ documentation of guideline-recommended SCS provided during antenatal care. Approximately, 4000 women who report smoking during pregnancy will be recruited across nine sites. The intervention and its implementation will be evaluated using a mixed methods approach. The primary outcome will be 7-day point prevalence abstinence at the end of pregnancy, among pregnant smokers, verified by salivary cotinine testing. Continuous data collection from electronic medical records and telephone interviews with postpartum women will occur throughout 32 months of the trial to assess changes in cessation rates reported by women, and SCS documented by clinicians and reported by women. Data collection to assess changes in clinicians’ knowledge, skills, confidence and attitudes will occur prior to and immediately after the intervention at each site, and again 6 months later. Questionnaires at 3 months following the intervention, and semi-structured interviews at 6 months with maternity service leaders will explore leaders’ perceptions of acceptability, adoption, appropriateness, feasibility, adaptations and fidelity of delivery of the MOHMQuit intervention. Structural equation modelling will examine causal linkages between the strategies, mediators and outcomes. Cost-effectiveness analyses will also be undertaken. Discussion: This study will provide evidence of the effectiveness of a multi-level implementation intervention to support policy decisions; and evidence regarding mechanisms of action of the intervention strategies (how the strategies effected outcomes) to support further theoretical developments in implementation science. Trial registration: ACTRN12622000167763, registered February 2nd 2022.

Smoking in pregnancy remains a public health challenge. Our team developed a comprehensive intervention using the Behaviour Change Wheel to support clinicians’ implementation of guidelines on supporting women to stop smoking in pregnancy. Integral to the intervention was a suite of evidence-based video and print materials. This paper describes the rationale and process for developing these materials. Comprehensive mixed methods research was undertaken to identify the key barriers and enablers for clinicians in implementing the guidelines. This research identified which behaviours required change, and which behaviour change techniques were best suited to effecting that change. Materials were developed based on this understanding, in a collaborative process with multiple stakeholders, and their feasibility and acceptability explored in a small trial. Materials developed included leadership, clinician and client resources. There are considerable advantages to systematically and collaboratively developing materials which are integral to a behaviour-change intervention even though it is resource intensive to do so.