Published online by Cambridge University Press: 06 July 2012
In the species Cavia the female passes into a condition of heat immediately, or almost immediately, after the birth of a litter, and pregnancy can be repeated without any interval. The new blastocysts reach the uterine cavity on the fifth day after parturition, and during the first seven days of pregnancy extensive reparative changes take place. These changes involve not only the healing of the placental site but a shedding and restoration of the epithelial lining of the uterus. As this process does not seem to have been investigated in detail in the guinea-pig, it is proposed in this paper to describe briefly the histological changes occurring in uteri at different times post partum in non-pregnant animals. It will be necessary, however, before describing the histological details of these post-partum changes to give a brief summary of the observations of other investigators on the ante-partum changes associated with the implantation of the blastocyst, the subsequent obliteration of the uterine cavity, the formation of the decidua capsularis, and the reappearance of the uterine lumen.