MEDICAL MEMORANDA MEDICALTISHURNAL 27 believe she was pregnant. Reckoning, somewhat academically be it admitted in view of this particular patient's irregular menstruation, on a 28-day cycle and a missed period, the date of onset coincided with the probable time of ovulation in the new cycle.Examination under anaesthesia was carried out. Nothing definite could be felt, but an impression was received of a vague soft swelling in the left fornix. Needling of the posterior fornix was contemplated but not undertaken, as the finding of blood in such a case would not have further clarified the diagnosis.The abdomen was opened under curarine and cyclopropane anaesthesia. A moderate amount of free blood was found in the pelvis. The uterus appeared normal in size and consistency. The left ovary was found to have a ruptured follicle which appeared to have been about the size of a marble. A half-handful of blood clot was adherent to this. Immediately adjacent was a dark swelling occupying approximately the base of what had been the follicle. A light prick of the scalpel showed the yellow convolutions of a recent corpus luteum. It seemed impossible to say whether one was dealing with one or two structures-a cystic corpus luteum of pregnancy or a ruptured Graafian follicle adjacent to a recent corpus luteum. The other ovary was normal in appearance. Apart from removing the blood clot and making sure that bleeding had ceased, nothing was done and the abdomen was closed.Next morning a specimen of urine was taken for an AschheimZondek test. On the third day the patient announced that she was menstruating. She had a painless loss, which ceased after four days. The Aschheim-Zondek test was reported weakly positive. Such a result can be obtained immediately before the onset of menstruation. In view of the events outlined it was thus interpreted at first. Two days later bleeding per vaginam was resumed and was followed by slight brownish discharge which continued. Finally on Aug. 8 curettage was undertaken and fragments of an early ovum were found in process of extrusion. Histological examination confirmed the presence of chorionic villi. Recovery thereafter was uneventful.The events subsequent to laparotomy make it clear that theemergency had been due to rupture of the corpus luteum of pregnancy. Whether or not this had been cystic it is impossible to say, as the normal size is known to have wide variations. It seems likely, though not necessarily conclusive, that the abortion was attributable to the impairment of the integrity of the corpus luteum from traumatic rupture.