The SoB intervention was created to address the overmedicalization of maternal care and excessive cesarean rates in Brazil [32], consistent with the Childbirth Humanization and RMC movements principles [1, 31]. The intervention, set in public spaces such as parks and street fairs, uses holograms, videos, role-playing, and other interactive techniques to offer the participants a childbirth experience. All participants are invited to walk through different sets as if pregnant and face the medicalized industries’ offers for childbirth. A detailed description of the intervention settings, methods, and implementation can be found in previously published papers of the Senses of Birth research team [32, 33].

Among the maternal care topics approached in the intervention are the intrapartum evidence-based practices. Evidence supporting these intrapartum practices is summarized in the WHO intrapartum care recommendations for a positive childbirth [3]. These practices are primarily, although not exclusively, dependent on the patient’s engagement. Thus, the SoB intervention was designed to address practices over which pregnant women have some degree of control or choice.

The intrapartum EBP discussed in the SoB intervention, and part of this study are: 1) creation and use of a birth plan; 2) one-to-one continuous support, including doula support and/or a companionship of choice throughout childbirth; 3) midwife care; 4) use of non-pharmacological pain relief methods; 5) freedom of mobility throughout labor; and 6) choice of position at delivery.

SoB is grounded in the Theory of Planned Behavior (TPB), and its proposed framework can be found in Sup. 1. TPB states that behavior can be directly influenced by the intention to engage in that behavior [34, 35]. The intention to perform a behavior is composed of attitudes, subjective norms, and perceived control over the behavior [35, 36]. Others have used TPB to understand childbirth and preference for the type of birth [37–40], although no studies were found focusing on its use with intrapartum EBP.

Perceived behavioral control is the individual’s perceived self-efficacy, that is, the confidence in their ability to perform the behavior [35, 36]. Such perception of control is built by internal factors (knowledge acquired and skills learned) and external factors (practical resources available, opportunities to use it, and the presence of other supportive conditions) [34–36]. For a woman to perceive that she can control the behavior of using the intrapartum EBP, therefore, increasing her intention to use it, she will need knowledge, skills, resources, and opportunities to increase her self-efficacy. The internal and external factors can facilitate or create challenges for a woman to use an EBP. As observed by previous results of the SoB impact on women’s knowledge, Brazilian women have moderate knowledge about normal birth and cesarean, and weak knowledge about EBP, although most perceived an increase in all three knowledge domains (normal birth, cesarean, and evidence-based practices) after the SoB intervention [41]. The impact of the SoB intervention on women’s perceived knowledge indicates a need to improve information regarding normal birth and cesarean, and an even higher need to discuss the use of evidence-based practices with pregnant women [41].