Neurovascular complications of ovarian hyperstimulation syndrome (OHSS): from pathophysiology to recent treatment options.

Ovarian hyperstimulation syndrome (OHSS) is a severe iatrogenic complication of ovulation induction, which has a very serious impact on the patient's health, as it is often associated with a high morbidity and mortality risk. Indeed, patients classified as having severe OHSS presented with liquid imbalance signs (such as rapid weight gain, tense ascites, respiratory difficulty and progressive oliguria), which are related to the fluid shift from the intravascular space to third space compartments subsequent to an increased capillary permeability. In this way, cardiovascular system findings include decreased intravascular volume, decreased blood pressure, decreased central venous perfusion, and compensatory increased heart rate and cardiac output with arterial vasodilation might be found concomitantly. Notwithstanding that venous thromboembolic phenomena are a possible complication in advanced phases of OHSS, arterial ischemia involving the cerebral circulation is a rare but recently reported problem. The pathogenesis of thromboembolism in OHSS is not fully understood, even though hemoconcentration and blood hyperviscosity seem to play a role in developing thrombotic changes into both venous and arterial system. Interestingly, the presence of cardiac abnormalities in combination with inherited or acquired hypercoagulable state seems to increase the risk of cerebral infarct in these subjects, as recently shown by our group. This review is aimed at investigating the pathomechanism and the management of neurovascular complications related to OHSS, including new treatment options.