THE MUSCULAR FIBRE AND CONNECTIVE TISSUE OF THE UTERUS. 373 



(Auflosung), and a new formation of young tissue in place of the old dead fibres," so that " a 

 female that has gone through pregnancy, and the puerperal state, possesses at the end of the 

 puerperium a new uterus." 



Heschl,* in reference to the human, says — " Of the uterus (which existed previous to labour) not 

 a single fibre remains behind." 



My observations lead to a quite opposite conclusion, viz., this change does not bring about a 

 destruction of the cells. Is is merely a transition from larger to smaller dimensions. There is no 

 destruction, no diminution in number, but simply the removal of some of their contents, a diminu- 

 tion in volume. It is an incomplete atrophy — not a numerical, but a simple physiological atrophy: 

 the process in each fibre goes on to a certain point, and then stops — the fibre remains, only it is of 

 a smaller volume. 



Under the view that the pregnant uterus at term was composed of two sets of muscle cells — 

 those that existed before conception occurred (greatly augmented during pregnancy) and those that 

 were newly developed during pregnancy — it became a question as to what fibres were attacked by 

 degeneration during the puerperium. Two distinct views are held : — (1) Kilian and Heschl (the 

 former basing his views on observations upon the rabbit's, the latter on the human, uterus) asserted 

 that all fibres were destroyed. (2) Others (e.g., KoLLiKER) offered the theory, that possibly the original 

 fibres were destroyed, and those of new development during pregnancy remained behind. 



This question is really settled by the observation that during pregnancy there is no new develop- 

 ment of young fibres, consequently the uterus at term is made up of fibres which are, so to speak, 

 contemporaries, and these fibres, which have all partaken in the great augmentation in volume of 

 pregnancy, now all undergo an equal diminution of volume in the puerperium. This change occurs 

 in all the muscle cells. 



2. Regeneration. — Prima facie, this complete destruction of one uterus, and the evolution of a 

 new organ, seems in the highest degree, and on clinical grounds alone, improbable ; for, as is well 

 known, the uterus that has once been pregnant remains after the puerperium of different form and 

 larger than the virgin uterus. And the above observations on the changes in the muscle cells show 

 that there is no need for new fibres to be formed. However, my preparations demonstrate the fact 

 that no new fibres are developed from pre-existing muscle cells — i.e., no nuclear figures are to be 

 discovered in any of the muscle cells. 



2. Connective Tissue. 



Concurrently with the changes in the muscle, there is also a change in the connective tissue, 

 but the processes differ. Contrary to the experiences of Meola, I can find no such rapid transition 

 of the connective tissue from a young to a riper state during the first days of the puerperium ; on 

 the other hand, my preparations show a decided gradual and progressive diminution in amount and 

 disappearance of the connective tissue. The process begins as an increasing granularity of the con- 

 nective tissue fibres and cells immediately post partum. Some of the connective tissue fibres during 

 the first three days swell up and become hyaline, eventually, however, breaking down into granules. 

 The connective tissue cells also become more and more granular, their nuclei are greatly changed, 

 breaking up into fragments which take on an intense colour when stained. In some cells there 

 also appear very fine fat granules — this especially in the sub-peritoneal connective tissue, but also in 

 some of the gland cells and sub-epithelial connective tissue cells also. In some places the destruc- 

 tion is so complete that all traces of connective tissue fibres are lost, their place being taken by a 

 clear mass, entangling granules and degenerating leucocytes and corpuscles and nuclei. Scattered 

 through this also are the large plasmodia. Other large connective tissue cells do not undergo this 

 degeneration. They are the large granular epithelioid cells with a single clear vesicular nucleus ; 

 already by the first day they are seen lying round the blocked capillaries, but on the 6th day they 

 are found to be almost filled with bright yellow granules derived from the disintegrating red blood- 



* " Untersuchungen iiber das Verhalten des menschlichen Uterus nach der Geburt," Zeit. der. Icais. kon. Gesellschaft 

 der Aerzte zu Wien, Jahrgang 8, Bd. ii. pp. 228, &c, 1852. 



