Abstract STUDY QUESTION What factors influence the decision-making process of fathers regarding multifetal pregnancy reduction or maintaining a triplet pregnancy, and how do these decisions impact their psychological well-being? SUMMARY ANSWER For fathers, the emotional impact of multifetal pregnancy reduction or caring for triplets is extensive and requires careful consideration. WHAT IS KNOWN ALREADY Multifetal pregnancy reduction is a medical procedure with the purpose to reduce the number of fetuses to improve chances of a healthy outcome for both the remaining fetus(es) and the mother, either for medical reasons or social considerations. Aspects of the decision whether to perform multifetal pregnancy reduction have been rarely investigated, and the impact on fathers is unknown. STUDY DESIGN, SIZE, DURATION Qualitative study with semi-structured interviews between October 2021 and February 2023. PARTICIPANTS/MATERIALS, SETTING, METHODS Fathers either after multifetal pregnancy reduction from triplet to twin or singleton pregnancy or ongoing triplet pregnancies 1–6 years after the decision were included. The interview schedule was designed to explore key aspects related to (i) the decision-making process whether to perform multifetal pregnancy reduction and (ii) the emotional aspects and psychological impact of the decision. Thematic analysis was used to identify patterns and trends in the father’s data. The process involved familiarization with the data, defining and naming themes, and producing a final report. This study was a collaboration between a regional secondary hospital (OLVG) and a tertiary care hospital (Amsterdam University Medical Center, Amsterdam UMC), both situated in Amsterdam, The Netherlands. MAIN RESULTS AND THE ROLE OF CHANCE Data saturation was achieved after 12 interviews. Five main themes were identified: (i) initial responses and emotional complexity, (ii) experiencing disparities in counselling quality and post-decision care, (iii) personal influences on the decision journey, (iv) ...