582 ACCIDENTS AFTER PARTURITION. 



ties maintain that there is no proof that this accident is more frequent 

 in animals suffering from inversion of the vagina than those which are 

 not. And it is to be remembered, as already stated, that the os must 

 be more or less dilated and dilatable for inversion of the uterus to 

 occur — a condition which does not always, nor yet frequently, co-exist 

 with vaginal inversion. The latter, indeed, is far from rare in non- 

 pregnant animals, and in those which have never been pregnant ; and 

 it is not at all uncommon in those which are advanced in pregnancy, and 

 yet do not suffer afterwards from this uterine displacement. 



Difficult and laborious parturition, when much manipulation and 

 jnergetic traction on the foetus have taken place, has likewise been 

 acknowledged as a cause of uterine inversion ; and it is certain that the 

 efforts to remove a fa3tus which, whether from malposition, deviation of 

 parts, excess of volume, etc., cannot be expelled in a natural manner, 

 are somewhat frequently followed by this accident. But on the other 

 hand, how often does it happen that the most vigorous — even painful 

 and violent — traction, and long and complicated manoeuvres, are not 

 succeeded by inversion ; while, on the contrary, the easiest and most 

 rapid birth sometimes is. 



The retention of the foetal placenta beyond the ordinary period, must 

 also be taken into account as one of the exciting causes ; as it then acts 

 as a foreign body, irritates the interior of the uterus, and so by a reflex 

 influence induces contraction of its muscular layer — this giving rise to 

 invagination of the extremity of one of the cornua, which is supposed 

 to be the commencement of inversion. 



It is also extremely probable that injudicious traction on the foetal 

 membranes may, for mechanical and physiological reasons, bring about 

 this result in a flaccid and dilated uterus, when the cervix is also re- 

 laxed. More especially is this likely to happen if the placenta is 

 adlierent towards the fundus of the organ, or in one of the cornua. 



Much mystery appears to have attached to this inversion of the 

 uterus, and though various causes have been assigned as operating in 

 its production, yet as these are not present in every case, it has been 

 admitted that a particular predisposition must have existed. 



It is evident that several causes may be invoked to account for the 

 accident. A flaccid, non-contracted uterus after birth, with a weak 

 cervix and dilated os, and relaxed broad ligaments, may be looked upon 

 as a predisposing condition ; and this is most likely to be present in 

 lymphatic animals, or those suffering from atony brought about by 

 debility from disease, bad or insufficient food, exposure to weather, etc. 

 When such a condition is present, it is easy to understand why inver- 

 sion may occur from abdominal pressure on the cornua or fundus of the 

 organ, or from external mechanical force ; and we can also comprehend 

 why an antiperistaltic movement of one of the cornua, or a portion 

 of it — just as happens in intussusception of the intestines — may take 

 place sometimes immediately after birth, and before the cervix has had 

 time to contract. Any trifling irritation may lead to this wrong move- 

 ment, and once commenced it is far more likely to continue than to 

 cease — as in the case of the intestines, when one portion becomes in- 

 vaginated within another. 



We believe this will be found to be the correct opinion. 



