The long term aim is to develop a comprehensive strategy in reducing the incidence and severity of OHSS in in-vitro fertilisation (IVF) cycles. Our short term aim (2-3 years) is to test the ability of the dopamine receptor agonist cabergoline in reducing the incidence and severity of OHSS in high risk women undergoing controlled ovarian hyperstimulation (COH) in fresh IVF cycles through a reduction in vasoactive cytokine levels, specifically in serum vascular-endothelial growth factor (VEGF).