On the other hand, the GnRH antagonist protocol has a reduced hazard of ovarian hyperstimulation syndrome (OHSS), which is a existence-threatening complication. The resulting prediction of e.g. bad or hyper-reaction to ovarian hyperstimulation establishes the protocol and dosage for ovarian hyperstimulation. It need to commence with reaction prediction by e.g. age, antral follicle rely and amount of anti-Müllerian hormone.