AIM: To explore the experiences of women who have had ovarian hyperstimulation syndrome, and healthcare professionals who care for them. BACKGROUND: Ovarian hyperstimulation syndrome is a side effect of fertility treatment. Little research exists internationally that explores the experiences of women who have had this condition, or the healthcare professionals who manage it. DESIGN: Qualitative study using semi-structured interviews. METHODS: Eighteen interviews with women who had experienced ovarian hyperstimulation syndrome (n = 10) and healthcare professionals (n = 8) in six UK fertility centres. Framework analysis was used. This paper is reported following COREQ guidelines. RESULTS: Women described a range of symptoms and severity, sometimes experiencing worrying physical health problems such as abdominal swelling and shortness of breath. The combination of the symptoms, and their management, on delaying future fertility treatment could cause emotional distress. Healthcare professionals at different centres described variation in practice, which generally involved 'active monitoring' until symptoms became severe, when women would be hospitalised. Women expressed feeling 'left in limbo' while waiting for symptoms to improve or worsen, and described a lack of control during this waiting period. Healthcare professionals felt they provided adequate information about ovarian hyperstimulation syndrome and its management. This, however, did not align with women's perceptions that information, including potential delays to their fertility treatment, was missing. There was similar mismatch between women's and healthcare professionals' views of decision-making about fertility treatment following ovarian hyperstimulation syndrome, including women's concerns about having to make rushed, unplanned decisions about their fertility treatment when they did not feel adequately informed to do so. CONCLUSION: Ovarian hyperstimulation syndrome and its management can have a significant physical and emotional impact on women, and influence their fertility treatment. Improvements could be made to the information women receive about this condition, its management and its implications for wider fertility treatment. IMPLICATIONS FOR THE PROFESSION AND/OR PATIENT CARE: Nurses have the skills and knowledge to support women through the physical and emotional stresses of fertility treatment. Therefore, they are well placed to provide specialist information and support for OHSS and ensure women are fully informed about all aspects of the condition, including how its management might delay fertility treatment.