ABDOMINAL PREGNANCY.
If an ovum falls from a Graafian follicle or from the smaller fimbria3 of the ovary into the abdominal cavity, and is or becomes impregnated and continues to develop, abdominal pregnancy is produced. In opposi tion to this idea is that in all of the described cases of abdominal preg nancy no early symptoms are known, so that they might have originated as tnbal pregnancies. In our observations on our own described cases of abdominal pregnancy we must admit that the ovum began its develop ment on the abdominal end of the tube. The fact that the placenta is occasionally found low in the pelvis speaks against this idea; but on the other hand, occasionally, in cases of large ovarian tumors, the is found lengthened and adherent so that the abdominal end is often as high as the navel.
According to Klob the ovum develops from the point where it is in contact with the abdominal wall, where cell proliferation of the connec tive tissue partly surrounds it, which through extraordinary vascularity makes it possible for a placenta to develop.
In rare cases the ovum is developed in the abdominal cavity without the formation of a pseudo-membranous sac, and there are many cases described where after the abdominal cavity is opened a developed foetus is found to be covered only with a thin transparent membrane.
Usually there are inflammatory processes in the neighborhood; false membranes form and must by further development rupture again and again, and new ones form. Thereby the ovisac at times becomes as thick as a pregnant uterus. The walls of the sacs are mostly composed of new-formed connective tissue, which becomes adherent with the intes tine, mesentery and rectum.
Hohl found in the walls of such a sac, that weighed 21 pounds, fibrillae that were not entirely cylindrical, but contracted when acetic acid was applied, and which he considered to correspond to the transverse fibres of the uterus; also indistinct organic muscular fibres were found on the posterior wall of the sac next to the uterus.
According to our opinion tubo-abdominal pregnancy is most favorable for advanced development, as by the formation of pseudo-membranes the neighboring structures become adherent to the sac, and prevent profuse bleeding, which is especially liable to occur in cases of tubal and interstitial pregnancy, where, after a certain size is reached, the outer covering, rich in blood-vessels, ruptures and death usually follows. In this variety the foetus usually reaches complete development, and is very often carried beyond the time of normal pregnancy.