Simultaneous occurrence of bilateral extrauterine pregnancy and hyperstimulation syndrome of the ovary following artificial heterologous insemination, meaning difficulty in the differential diagnosis, is described. In connection with the case the protocol of induction of ovulation used regularly by the authors is presented and the necessary monitoring model is described. If the observation is suitable the emergency operation of a patient in bad physical condition can be avoided in the opinion of the authors. The close correlation between the hyperstimulation of the ovary and early-pregnancy as well as the favourable spontaneous healing disposition of the cystic alteration is highlighted. It is held important that a laparotomy performed in connection with acute abdominal symptoms should be conservative for the genitals--possibly even in case of extrauterine pregnancy--in order to maintain the chances for a later fertility.