PELVIS MINOR 



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apparent in the infant, becomes less distinct as puberty 

 approaches, and usually disappears altogether after parturition. 

 This constriction is called the isthmus. 



Cervix Uteri. The cervix, or neck, of the uterus is about 

 2 5 mm. (one inch) in length ; it is narrower than the body and 

 more cylindrical in form. It projects into the upper end 

 of the vagina, the walls of which are attached around it. 



To obtain a satisfactory view of the relation of the uterus 

 to the vagina, both organs should now be split sagittally, 

 care being taken to avoid injuring the rectum. When the 

 section has been made, the posterior wall of the vagina will 

 be found to ascend to a higher level on the cervix than the 

 shorter anterior wall (Figs. 224, 229). On the lower extremity 

 of the cervix, which rests against the posterior vaginal wall, 

 there is an orifice, the orificium externum uteri (O.T. os uteri 

 externum). The orifice, in nulliparae, is always a small 

 transverse slit, with rounded anterior and posterior lips, but in 

 women who have borne children it is usually larger, and 

 its margins are more irregular in outline. The anterior lip 

 is the shorter, and it is placed at a lower level in the vagina. 

 The difference in the level and in the length of the two lips is 

 due to the fact that the uterus passes obliquely through the 

 vaginal wall. The part of the cervix which projects into the 

 vagina is the vaginal portion ; the part above is termed the 

 supravaginal portion. 



Cavum Uteri. The cavity of the uterus is separable into 

 two parts, the cavity of the body and the cavity of the cervix. 

 The cavity of the body is a mere cleft, triangular in outline, 

 which lies between the anterior and posterior walls. The 

 base of the triangle is above, and at each of its angles a 

 uterine tube opens into the cavity. The apex is below, 

 where the cavity of the body joins the cavity of the cervix, at 

 a constricted aperture of communication called the ortfaium 

 internum uteri (O.T. os uteri internum). 



The cervical portion of the cavity is spindle-shaped and 

 slightly compressed from before backwards. It extends from 

 the internal orifice, where it is continuous with the cavity of 

 the body, to the external orifice, where it opens into the 

 vagina. 



The Relations of the Uterus. The posterior surface of the 

 uterus is completely covered with peritoneum, and it is separated 

 from the rectum by the recto-vaginal pouch, in which lie 



