On the other hand, the GnRH antagonist protocol has a reduce risk of ovarian hyperstimulation syndrome (OHSS), which is a life-threatening complication. The ensuing prediction of e.g. bad or hyper-reaction to ovarian hyperstimulation decides the protocol and dosage for ovarian hyperstimulation. It should start out with response prediction by e.g. age, antral follicle depend and degree of anti-Müllerian hormone.