Prevention and management of ovarian hyperstimulation syndrome.

Ovarian hyperstimulation syndrome is a relatively common complication of ovarian stimulation and can be life-threatening. The pathophysiology of ovarian hyperstimulation syndrome is characterised by increased capillary permeability, leading to leakage of fluid from the vascular compartment, with third space fluid accumulation and intravascular dehydration. The combined use of a gonadotrophin-releasing hormone antagonist protocol with gonadotrophin-releasing hormone agonist triggering and oocyte and embryo freezing has considerable promise in preventing ovarian hyperstimulation syndrome. Women with severe ovarian hyperstimulation syndrome require hospitalisation for more careful monitoring and treatment. Transvaginal paracentesis can be used as an outpatient treatment to prevent the need for hospitalisation. The inhibition of vascular permeability seems to be a novel therapeutic approach to preventing and treating ovarian hyperstimulation syndrome.