KI2 HUMAN ANATOMY. 





^^ 



lm . 44,. If. on the contrary, fertilization does not occur the proh erative 



and the hv,>ertrophied mucosa (now railed the deddua mtnstruatis) 

 Incidental to the latter are subepithelial extravasation and rupture and 

 ,: ,h, epithelium. foil, .wed by the characterise discharge of blood. \\ hile 

 :rm-ti.,ii of the mucosa is limited to the epithelium, it is probable that at times 



.,1 the subjacent tissue is involved. 



i Hiril ,.- the in. ,st c. .nspicuous changes are occasioned by the growth necessary 



to accomm.-date the rapidly augmenting volume of the uterine contents, by the provision of an 



mtrition ami protection for the fetus, and by the development of an efficient 



:hr expulsion of the same. From an organ ordinarily weighing about 



. , ir j n} , 7 cm. in length and possessing a capacity of from 3-5 cc., by the 



:!ie uterus has expanded into a rounded or oval sac about 36 cm. (14 in.) in 



: ( ,m 900-1000 grm. (about 2 Ibs.) in weight and with a capacity of 5000 cc. 



more. This enormous increase depends especially upon the hypertrophy of the 



in, which during the first half of pregnancy becomes greatly thickened, 



Init later thinner and membranous owing to stretching. The increase in this coat results from 



IHI ,|. ;, of the i>revi..usly existing muscle-cells and, during the first half of pregnancy, 



.pin.-nt .f iu-w muscle elements. The individual cells may increase tenfold in length 



5 mm. Although the cervix actually almost doubles in size, its growth 



is \. ,1 |,y that of the In.dy, since it remains relatively passive. During the first five 



:hs, the mucous membrane of the Ixxjy of the uterus also becomes greatly hypertrophied, 



;,, -..in- a thickness from 7-10 mm. The glands and blood-vessels, particularly the 



id, within the socialized area, are concerned in the formation of the placenta 



(page 48). The cervical mucosa takes no direct part in the formation of the deciduae, although 



it t! -In- s,-.it .,f enlarged glands that secrete the plug of mucus that for a time 



occludes the mouth of the uterus. 



nination of pregnancy, the uterus enters upon a period of involution and 



muscular ti sue undergoing degeneration and absorption and the lacerated 



ration, the latter process being completed in from five to six weeks (Minot). In 



r.iwth of tin- imometrium, the round ligaments enlarge and also show marked 



t ion of their muscular tissue. The peritoneal relations are disturbed by the excessive 



.- uti-rus. s, . th.it at the sides the layers of the broad ligament become separated. 



Variations. The chief anomalous conditions of the uterus depend upon defective devel- 



t fusion of the Miillerian ducts by the union of which the normal organ is 



-ted development of the lower part of these fietal canals accounts for entire ab- 



.uul vagina. I '('pending upon the extent to which failure of fusion occurs, 



all degr- -odiKi-d. In the most pronounced cases, in which the Miillerian 



.! throughout their entire length, two completely distinct uteri and vagina- 



r Ix-ini; capable of performing the functions of tin- normal organs. On the 



id, slight indentation of the Hindus may be the only evidence of imperfect union. Be- 



ur; the body maybe completely cleft I uterus bicornis I, 



with i.r without dh the duplicity may be partial and limited to branching of the 



e manifested by onlv a partition, more or less complete, that 



ompartments (uterus status], although tlu- external form of 



or i|uite normal. When, in conjunction with any of the foregoing variations, 



t "f tin- CO1 ' illeri.m dints fails to keep p.i, -,- in its growth, all decrees of asymmet- 



-ult. froin complete suppression of one of the tubes in a bicornate uterus 



uiution of the fundus. Subsequent arrest of what to a certain stage was 



normal <! VK ,ult in permanent retention of the fu-tal or infantile type of uterus. 



rSIDERATIONS: ITERUS AND ITS ATTACHMENTS. 



pelvis is subdivided into two compartments by a fold of peri- 



!r.,in the tlo, r , m .l sides of the cavity. This fold passes from one 



n its lavers in the median line the uterus. On 



each side of the uterus it is known as the broad liniment, and encloses the uterine 



