The sudden cessation of the breeding symptoms, with sense of weight and coldness in the lower part of the belly, flaccid breasts, pain in the back and loins, and discharge of blood from the uterus, are pretty sure signs of abortion: they are those which are "produced by separation of the ovum and contraction of the uterus," (_Burns_;) the one is attended by hæmorrhage, the other by pain. Although these are two chief symptoms which characterize a case of threatened abortion, and although they must necessarily be present more or less in every instance where premature expulsion actually happens, still neither of them, either separately or conjointly, can be considered as a certain proof that the uterus will carry its contents no longer. Cases not unfrequently happen where patients have repeated attacks of hæmorrhage during the early months of pregnancy, and sometimes to a considerable amount, without any apparent disturbance to the process of gestation, and are delivered of a living healthy child at the full term: on the other hand, we have known instances where the pain of the back was severe, and where, on assuming the erect posture even for a minute, the sense of weight and bearing down in the lower part of the abdomen was so great as to make the patient fear that the ovum was on the point of coming away; still even these threatening symptoms have gradually subsided, and the pregnancy has continued its natural period. Puzos considered that neither pain nor hæmorrhage were necessarily followed by expulsion. (_Mém. de l'Acad. de Chir._ vol. i. p. 203.) When, however, both occur together, and to a considerable extent, the case must be looked upon as one of at least doubtful if not unfavourable termination. Where pain comes on at regular intervals, with hardness of the uterus, and dilatation of its mouth, this is a serious symptom, for it shows that the uterus will no longer retain its contents, but is evidently preparing to expel them.