Moderate ovarian hyperstimulation syndrome complicated by deep cerebrovascular thrombosis.

This report describes two cases that developed moderate ovarian hyperstimulation syndrome (OHSS) without evidence of haemoconcentration. Both patients developed serious cerebrovascular thrombosis resulting in hemiparesis, and recovered after treatment with anticoagulants. This report emphasizes that other factors may contribute to vascular thrombosis, and illustrates that cerebrovascular accidents may complicate even moderate OHSS.