PRACTICAL CONSIDERATIONS : THE VAGINA. 2019 



the mucous membrane of the lower third with greater sensibiHty and send motor fila- 

 ments to the striated muscle surrounding the entrance. Sensory nerve-endings of 

 different kinds have been described within the mucosa. 



Development. — The vagina is formed by the downward extension and fusion 

 of the Miillerian ducts. After union of the latter with the posterior wall of the uro- 

 genital sinus and the appearance of a lumen, which at first is wanting, the genital 

 canal opens into the sinus by an aperture, later the orificium vaginae, that lies between 

 and closely united with the Wolffian ducts. The latter subsequently atrophy and 

 disappear, but may, in exceptional cases, persist to a greater or less extent as Gart- 

 ner's ducts. The entrance of the immature vagina is early guarded by an annular 

 fold that becomes the hymen and owes its differentiation to a pouching of the vaginal 

 wall behind a zone of thickened epithelium (Nagel). For a time, usually until about 

 the seventh month of foetal life, the orifice of the vagina is occluded by epithelium. 

 The proliferation and thickening of the vaginal lining, which begin below, gradually 

 extend upward and result in the production of conspicuous rugje, which, during the 

 last months of pregnancy, cover not only the entire surface of the vagina, but also 

 that of the cervix, which even at birth is slightly corrugated. In consequence of the 

 increasing irregularity and thickening of the mucosa, the vaginal walls, which for a 

 time are adherent, become separated and the lumen of the canal is definitely estab- 

 lished, remains of the desquamated epithelium being often visible in the new-born 

 child. Distinct muscular tissue within the vaginal wall is not distinguishable before 

 the fifth month. 



At birth, the vagina is relatively long (Fig. 1623) and its wall is comparatively 

 thick, with conspicuous rugae extending as far as the vault. During the early years 

 of childhood the vagina remains small and vertical, but after the tenth year grows 

 rapidly, the increased width causing reduction in the rugae, which from now on are 

 feebly marked in the upper part of the canal. After undergoing the stretching inci- 

 dent to labor, the rugae and columns are much less conspicuous, and after repeated 

 distention may suffer almost complete effacement. The vagina shares in the general 

 involution of the sexual organs, and in advanced years loses much of its former elas- 

 ticity and undergoes atrophy. 



Variations. — The most important variations depend upon defective development and im- 

 perfect fusion of the component Miillerian ducts, and are, therefore, often associated with 

 anomalies of the uterus. When these tubes fail to reach the urogenital sinus, the vagina ends 

 blindly above the vestibule ; or when their lower segments are stunted, the vagina (and often 

 uterus) may be entirely wanting. Duplication, more or less complete, follows persistence of 

 separate or imperfectly fused Miillerian ducts. The doubling may not extend throughout the 

 length of the vagina, but may be represented by an imperfect and partial septum, isolated bands, 

 or a twin hymen. Unequal development of the Miillerian ducts accounts for the marked asym- 

 metry occasionally observed, notably in double vaginae, where one canal may be very rudi- 

 mentary or end blindly. The hymen presents great variety in the details of its opening, which 

 may be crescentic, circular, stellate, linear, double, or multiple {hymeti cribriformis) . It may 

 be a mere pin-hole or entirely wanting (imperforate), in which case retention of menstrual dis- 

 charges occurs. 



PRACTICAL CONSIDERATIONS : THE VAGINA. 



Congenital malformations of the vagina, such as absence of the vagina, rudi- 

 mentary vagina, or vaginal septa, are usually associated with corresponding errors 

 in development of the uterus. While other malformations due to faulty union of the 

 Miillerian ducts occur, the more common is a uterus bicornis, or a double uterus and 

 vagina. They are not incompatible with pregnancy, labor and the puerperium often 

 passing without unusual incident ; indeed, this conditioft is usually recognized by 

 accident, since no external evidence is seen. Conception may occur on one or both 

 sides simultaneously. A vaginal septum which interfered with the progress of the 

 head should be divided. From imperfect development of one side of a bicornate 

 uterus, pregnancy may lead to great danger of rupture of the weak uterine wall, or 

 to a failure to expel the child. 



While varying within normal limits with the distention of the bladder, when the 

 latter is empty the axis of the fundus of the uterus lies at about a right angle with 

 the vagina. The inner or uterine end of the broad ligament is, except at its base, 



