Preventing ovarian hyperstimulation syndrome: guidance for the clinician

Objective: To reevaluate ovarian hyperstimulation syndrome (OHSS) prevention techniques and provide a classification system for grading OHSS and evidence-based treatment strategies for preventing OHSS. Design: A literature search was conducted in PubMed for articles published in the last 5 years using the keywords controlled ovarian stimulation, controlled ovarian hyperstimulation, ovarian hyperstimulation syndrome, OHSS, prevention, chorionic gonadotropin, hCG, GnRH agonist, GnRH antagonist, coasting, and cryopreservation. We reviewed randomized controlled trials (RCTs), retrospective studies, pilot studies, case studies, reviews, and meta-analyses. Result(s): There is a shortage of large, prospective RCTs reporting OHSS prediction and prevention strategies. Our review showed that risk factors such as antral follicle count and baseline anti-Mullerian hormone level may identify women at high OHSS risk. Preventative strategies that appear highly effective at reducing or preventing OHSS include GnRH antagonist protocols and the use of GnRH agonists to trigger final oocyte maturation. Moreover, alternative therapies, such as dopamine receptor agonists (Cabergoline), have also emerged as potential new treatment modalities in the management of this disease. Conclusion(s): These findings suggest that current treatment guidelines should be updated to incorporate findings from recent literature that show that GnRH antagonist protocols consistently reduce OHSS and that GnRH agonist triggering has considerable promise in preventing OHSS, although further RCTs will be needed to confirm this. (Fertil Steril(R) 2010;94:389-400. (C) 2010 by American Society for Reproductive Medicine.)