Inm-10: OHSS Management Procedure and Results

The ovarian hyperstimulation syndrome (OHSS) is a consequence of superovulation therapy for assisted conception procedures. This potentiallyfatal condition is avoidable by the judicious use of gonadotropins and carefulmonitoring of stimulation regimens. Women who are at particular risk ofdeveloping the syndrome include those who have polycystic ovaries and thosewho are young (under 30 years). We have clear protocols for identifying patients at risk both before and during ovarian stimulation which are in place for the management of patients who develop symptoms. Information is provided to patients within the general pre-treatment information leaflets and also after the egg collection, so that they are aware of the risk and the symptoms to be aware of. We keep a record of cases of OHSS, with particular note of patients who require hospitalization incorporated in standard risk management protocols. We ensure appropriate follow up of patients after embryo transfer and during pregnancy. Mild ovarian hyperstimulation is managed expectantly; Patients with Grade 2 hyperstimulation need reassurance and explanation, together with bed rest in hospital. The development of clinically detectable and usually painful ascites, together with deterioration in respiration, circulation and renal function indicates the development of severe Grade 3 hyperstimulation and may require admissionto an intensive care unit. The intravascular volume is monitoredby measurements of central venous pressure, renal function by meticulousattention to input and urine output and haemoconcentration by measurementof haematocrit, whose level reflects intravascular volume depletion and bloodviscosity. Infusion of colloid (e.g. human albumen or 6% hydoxyethyl starch (HES) isrequired to maintain intravascular volume, as indicated by restoration ofnormal central venous pressure. Crystalloid (normal saline usually) is administered for rehydration with careful monitoring of fluid balance. Prophylactic heparin is given to prevent thromboembolism and continues up to the end of the first trimester of pregnancy. We try to minimize the risk of OHSS by using low doses of gonadotropinsand reducing doses in women with polycystic ovaries. If an exuberant ovarianresponse is observed then the dose of gonadotropin would be reduced furtherand the dose of hCG also reduced or hCG not administered.