This case report describes a lady who presented with abdominal pain, hypotension and multiple ovarian follicles following egg collection and embryo transfer. She was provisionally diagnosed with Ovarian Hyperstimulation Syndrome (OHSS) and managed accordingly. This case study describes her clinical presentation, investigations, progress, management and outcome. No current laboratory diagnostic/prognostic markers are available for OHSS; the condition is currently diagnosed clinically. The subsequent discussion elaborates on the epidemiology, pathophysiology, clinical features, assessment, management and risk factors of OHSS, and aims to increase awareness of this important complication of infertility treatment to assist diagnosis, prevention and early institution of treatment.