This British Fertility Society (BFS) Policy and Practice guideline aims to support clinicians in preventing ovarian hyperstimulation syndrome (OHSS) in patients undergoing gonadotropin ovarian stimulation. A systematic literature search of the medical databases was performed. The Guideline Development Group (GDG) identified the risk factors of OHSS before and during ovarian stimulation. The relation of different pre-treatment measures and different ovarian stimulation protocols with OHSS was evaluated. The optimal monitoring during treatment was assessed. The current evidence on preventive strategies during and after ovarian stimulation and the available adjuvant preventive agents were examined. Based on this, the GDG developed evidence-based, graded recommendations for clinical practice. The evidence was evaluated within context, considering the effectiveness, cost and practical problems of assisted reproductive technology for patients and healthcare providers. Early identification and application of preventive measures identified in this guideline may reduce the incidence of OHSS or reduce its severity. Suggestions for future research on OHSS prevention are provided.
Keywords: Ovarian hyperstimulation syndrome; assisted reproductive technology; gonadotropins; ovarian stimulation; prevention.