ABSTRACT

The ovarian hyperstimulation syndrome (OHSS) is characterized by an increase in size of the ovaries, with the appearance of multiple cysts, and by an increase in the vascular perme­ ability of ovarian vessels causing ascites, pleural effusion and sometimes pericardiac effusion. The severe form is also accompanied by elec­ trolyte disturbances, as well as by cardio­ pulmonary, hepatic, renal and hemodynamic disturbances, leading to an increased thrombo­ embolic risk. The dominant finding is bilateral multicystic enlargement of the ovaries. Morpho­ logical examination of these ovaries reveals multiple corpora lutea, follicle cysts and mas­ sive edema of the ovarian stroma. It has been suggested that formation of the cysts is a direct reaction to stimulation with gonadotropins, since similar ovarian observations exist in other conditions associated with high levels of endogenous gonadotropins such as hydatidiform mole, choriocarcinoma and multiple pregnancy.