Background <p>Freedom of movement and choice of position during labor are associated with improved labor progress, maternal and neonatal outcomes, and more positive birth experiences. However, mobility is often restricted in hospital settings. Antenatal preparation may help women develop the knowledge, confidence, and skills needed to make informed decisions about mobility during labor. This paper reports the development of a complex intervention designed to support such decision-making.</p> Methods <p>The intervention was developed in line with the Medical Research Council (MRC) framework for complex interventions. The preparatory phase included a scoping review, in-depth interviews with nurse-midwives and pregnant women, and focus groups with childbirth preparation experts to explore context, needs, barriers, facilitators, and current practices. Findings from these sources were synthesized in a workshop to draft the intervention, followed by a second workshop with researchers and nurse-midwives to refine and validate its structure and content.</p> Results <p>The intervention, entitled <i>I choose to move during my labor</i>, was developed iteratively with input from nurse-midwives, researchers, experts, and pregnant women attending Childbirth Preparation Programs in Community Care Units. It integrates evidence from the preparatory phase and emphasizes experiential learning, communication, and support for informed decision-making. The final intervention comprises four core components: group sessions, experiential learning activities, decision-making support, and a facilitative communication environment.</p> Conclusion <p>This MRC-guided intervention provides a theory-informed and context-sensitive approach to supporting women’s informed decision-making about mobility during labor within antenatal education settings, while offering a foundation for future feasibility testing and implementation.</p>