Ovarian hyperstimulation syndrome.

Ovarian hyperstimulation syndrome is an iatrogenic complication of assisted reproduction. In its most severe form, it is potentially fatal. The major clinical components are marked ovarian enlargement and increased capillary permeability leading to ascites, hydrothorax and pericardial effusion. Severe cases are associated with thromboembolic phenomena, respiratory distress and renal failure. The definitive pathophysiology is unknown. The available evidence would support a central role for inflammatory cytokines and angiogenic growth factors. Ultrasound examination and serum oestradiol values are currently used to predict patients at risk. The ideal treatment is prevention, but there has been only limited success. The main aims of treatment are to correct fluid imbalance, maintain renal perfusion and support the patient until the condition resolves. Drug therapy has a limited role, although anticytokine agents may prove useful.