THE UTERUS 1259 



In the virgin state the uterus is flattened antero-posteriorly and is pyriform 

 in shape, with the apex directed downward and backward. It lies between the 

 bladder in front and the pelvic or sigmoid colon and rectum behind, and is com- 

 pletely within the pelvis, so that its base is below the level of the superior pelvic 

 aperture. Its upper part is suspended by the broad and the round ligaments, 

 while its lower portion is imbedded in the fibrous tissue of the pelvis. 



The long axis of the uterus usually lies approximately in the axis of the superior 

 pelvic aperture, but as the organ is freely movable its position varies with the 

 state of distension of the bladder and rectum. Except when much displaced by a 

 fully distended bladder, it forms a forward angle with the vagina, since the axis 

 of the vagina corresponds to the axes of the cavity and inferior aperture of the 

 pelvis. 



The uterus measures about 7.5 cm. in length, 5 cm. in breadth, at its upper 

 part, and nearly 2.5 cm. in thickness; it weighs from 30 to 40 gm. It is divisible 

 into two portions. On the surface, about midway between the apex and base, 

 is a slight constriction, known as the isthmus, and corresponding to this in the 

 interior is a narrowing of the uterine cavity, the internal orifice of the uterus. The 

 portion above the isthmus is termed the body, and that below, the cervix. The 

 part of the body which lies above a plane passing through the points of entrance 

 of the uterine tubes is known as the fundus. 



Body (corpus uteri) . The body gradually narrows from the fundus to the 

 isthmus. 



The vesical or anterior surface (fades vesicalis) is flattened and covered by 

 peritoneum, which is reflected on to the bladder to form the vesicouterine 

 excavation. The surface lies in apposition with the bladder. 



The intestinal or posterior surface (fades intestinalis) is convex transversely and 

 is covered by peritoneum, which is continued down on to the cervix and vagina. 

 It is in relation with the sigmoid colon, from which it is usually separated by some 

 coils of small intestine. 



The fundus (fundus uteri} is convex in all directions, and covered by peritoneum 

 continuous with that on the vesical and intestinal surfaces. On it rest some coils 

 of small intestine, and occasionally the distended sigmoid colon. 



The lateral margins (mar go later alis} are slightly convex. At the upper end of 

 each the uterine tube pierces the uterine wall. Below and in front of this point 

 the round ligament of the uterus is fixed, while behind it is the attachment of the 

 ligament of the ovary. These three structures lie within a fold of peritoneum 

 which is reflected from the margin of the uterus to the wall of the pelvis, and is 

 named the broad ligament. 



Cervix (cervix uteri; neck). The cervix is the lower constricted segment of 

 the uterus. It is somewhat conical in shape, with its truncated apex directed 

 downward and backward, but is slightly wider in the middle than either above or 

 below. Owing to its relationships, it is less freely movable than the body, so that 

 the latter may bend on it. The long axis of the cervix is therefore seldom in the 

 same straight line as the long axis of the body. The long axis of the uterus as a 

 whole presents the form of a curved line with its concavity forward, or in extreme 

 cases may present an angular bend at the region of the isthmus. 



The cervix projects through the anterior wall of the vagina, which divides it 

 into an upper, supravaginal portion, and a lower, vaginal portion. 



The supravaginal portion (portio supravaginalis [cervicis]) is separated in front 

 from the bladder by fibrous tissue (parametrium), which extends also on to its sides 

 and lateralward between the layers of the broad ligaments. The uterine arteries 

 reach the margins of the cervix in this fibrous tissue, while on either side the ureter 

 runs downward and forward in it at a distance of about 2 cm. from the cervix. 

 Posteriorly, the supravaginal cervix is covered by peritoneum, which is prolonged 





