Pathophysiology, treatment and prevention of ovarian hyperstimulation syndrome

Purpose of review Severe ovarian hyperstimulation syndrome (OHSS) is an iatrogenic condition that affects 1% of women that undergo treatment with assisted reproductive technology. The review aims to summarize recent evidence on pathophysiology, treatment, and prevention of OHSS. Recent findings The pathophysiology is still not completely understood; however, vascular endothelial growth factor is likely to be an important mediator. Human chorionic gonadotropin was previously thought to be necessary for OHSS to occur; however, recent case reports have proven otherwise. The contribution of an attenuated anti-Mullerian hormone signalling pathway and CD11c + HLA-DR + dendritic cells and associated interleukins has been explored recently as contributors to pathogenesis. Treatment is largely supportive and is based mainly on consensus statements rather than evidence. Therefore, it is important to prevent this condition by identifying women at risk, allowing the clinician to implement preventive strategies, including the use of GnRH antagonist cycles with agonist triggers. Summary More research is required to elucidate the pathophysiology behind the condition. Clinicians should employ strategies to prevent OHSS.