Embryo freezing for preventing Ovarian Hyperstimulation Syndrome.

Ovarian hyperstimulation syndrome (OHSS) is an iatrogenic potentially life threatening condition resulting from an excessive ovarian stimulation. Its reported incidence varies from 1% to 10% of in vitro fertilization (IVF) cycles. The factors leading to this syndrome have not been completely explained. It seems likely that the release of vasoactive substances, secreted by the ovaries under human chorionic gonadotropin (hCG) stimulation plays a key role in triggering this syndrome. The hallmark of this condition, is a massive shift of fluid from the intra-vascular compartment to the third space resulting in profound intra-vascular depletion and hemoconcentration.