Twenty second meeting. 



Rockefeller Institute for Medical Research. April iy, 190J. Presi- 

 dent Flexner in the chair. 



64 (207) 



Wounds of the pregnant uterus. 



By LEO LOEB. 



[From the Laboratory of Experimental Pathology, University of 



Pennsylvania^ 



In continuation of former experiments to determine the influence 

 of functional conditions upon processes of cell growth and cell ne- 

 crosis in the ovaries, investigations of a similar character were under- 

 taken on the pregnant uterus of the guinea pig. As is well known, 

 the pregnant uterus responds to the stimulation of the fertilized 

 ovum by the production of decidual tissue. It was thought possible 

 that in the beginning of pregnancy the uterus might respond also 

 to other stimuli such as wounds, in a way different from the ordi- 

 nary uterus. Experiments were carried out in twenty six guinea 

 pigs at different stages of pregnancy. Wounds were made in various 

 directions in the uterus, or part of the wall of the uterus was in- 

 verted so that the mucous membrane was turned outside. It was 

 found that at a certain stage of pregnancy, namely from the fourth 

 to the sixth day, nodules of decidual tissue were formed at places 

 where the continuity of the uterus had been interrupted or where 

 the mucous membrane had been inverted. Serial sections of these 

 nodules show that they consist of typical decidual tissue which does 

 not include a developing ovum. The number of these nodules was 

 either larger than the number of corpora lutea present in the ovaries 

 which had been cut into serial sections or in other cases corpora 

 lutea were present on only one side of the animal while the decidual 

 nodules were present in both horns of the uterus. Under those 

 conditions it is not likely that the formation of the decidual nodules 

 was caused by the direct stimulation of an ovum, but it is more 

 likely that, at the period of pregnancy, when the development of 



(93) 



