THE UTEItls. 



1173 



Vessels and Nerves. The arteries of tin- n.t> /" are the uterine, from the internal 

 iliac, and the ovarian, from the aorta. They are remarkable for their tortuous 

 course in the substance of the organ and for their frequent anastomoses. The 

 termination of the ovarian artery meets the termination of the uterine artery, and 

 forms an auastomotic trunk from which branches are given off to supply the 

 uterus, their disposition being, as shown by John Williams, circular. The veins 

 are of large size, and correspond with the arteries. In the impregnated uterus 

 these vessels are termed the uterine sinuses, consisting of the lining membrane of 

 the veins adhering to the walls of the canal channelled through the substance of 

 the uterus. They terminate in the uterine plexuses. The lymphatics of the body 

 terminate in the lumbar glands, those of the cervix in the pelvic glands. The 



Internal iliac 

 artery. 



FIG. 751. The arteries of the internal organs of generation of the female, seen from behind. (After HyrtL) 



nerres are derived from the inferior hypogastric and ovarian plexuses, and from 

 the third and fourth sacral nerves. 



The form. size, and situation of the uterus van* at different periods of life and under dif- 

 ferent circumstancfs. 



/// the ffftiis the uterus is contained in the abdominal cavity, projecting beyond the brim of 

 the pelvis. The cervix is considerably larger than the body. 



At pf:rty the uterus is pyriform in shape, and weighs from eight to ten drachms. It has 

 descended into the pelvis, the fundus being just below the level of the brim of this cavity. The 

 arbor vita? is distinct, and extends to the upper part of the cavity of the organ. 



During m?i<xti-n<it!on the organ is enlarged, and more vascular, its surfaces rounder : the 

 termini is rounded, its labia swollen, and the lining membrane of the body thickened, 

 .-otter and of a darker color. According to J. Williams, at each recurrence of menstruation a 

 molecular disintegration of the mucous membrane takes place, which leads to its complete 

 removal, only the bases of the glands imbedded in the muscle being left. At the cessation 

 of menstruation by a proliferation of the remaining structures a fresh mucous membrane is 

 formed 



During pregnancy the uterus becomes enormously enlarged, and in the ninth month reaches 

 the epigastric region. The increase in size is partly due to growth of pre-existing muscle and 

 partly to development of new fibres. 



^ Aft.fr j:irtur>'tion the uterus nearly regains its usual size, weiebine about an ounce and a 

 half: but its cavity is larger than in the vinrin state, the external orifice is more marked, its 

 ed<.:es present a fissured surface, its vessels are tortuous, and its muscular layers are more 

 defined. 



