INTRODUCTION Appropriate use of interventions in maternity care is a worldwide issue. Midwifery-led models of care are associated with more efficient use of resources, fewer medical interventions, and improved outcomes. However, the use of interventions varies considerably between midwives. The aim of this study was to explore how knowledge and skills influence clinical decision-making of midwives on the appropriate use of childbirth interventions. METHODS A qualitative study using in-depth interviews with 20 primary care midwives was performed in June 2019. Participants’ clinical experience varied in the use of interventions. The interviews combined a narrative approach with a semi-structured question route. Data were analyzed using deductive content analysis. RESULTS ‘Knowledge’, ‘Critical thinking skills’, and ‘Communication skills’ influenced midwives’ clinical decision-making towards childbirth interventions. Midwives obtained their knowledge through the formal education program and extended their knowledge by reflecting on experiences and evidence. Midwives with a low use of interventions seem to have a higher level of reflective skills, including reflection-in-action. These midwives used a more balanced communication style with instrumental and affective communication skills in interaction with women, and have more skills to engage in discussions during collaboration with other professionals, and thus personalizing their care. CONCLUSIONS Midwives with a low use of interventions seemed to have the knowledge and skills of a reflective practitioner, leading to more personalized care compared to standardized care as defined in protocols. Learning through reflectivity, critical thinking skills, and instrumental and affective communication skills, need to be stimulated and trained to pursue appropriate, personalized use of interventions.