This article summarises the ultrasound features of a number of gynaecological emergencies: ectopic pregnancy, haemorrhagic corpus luteum, twisted adnexa, pelvic inflammatory disease, acute myoma necrosis, haematocolpos and haematometra. The basis of all diagnosis in women with acute gynaecological conditions is history and clinical examination. An ultrasound examination should only be performed if it is likely to provide information that would change the likelihood of the diagnosis suspected on the basis of clinical data. If ultrasound findings are abnormal, then it is important to thoroughly evaluate if they do explain the woman's symptoms or if they are merely an incidental finding. If ultrasound findings are completely normal, then the risk of significant pelvic pathology is probably small.