According to _Waldeyer_, the bursting of the follicle is not to be regarded as dependent upon a sudden rise of pressure in its interior, but as the result of a gradual ripening process. At the deepest pole of the follicle, which in the course of its development has now approached the surface of the ovary, an exuberant growth takes place in the internal layer (tunica propria) of the theca folliculi, with a profuse formation of new vessels. Here numerous “epithelioid” cells, the “lutein-cells,” make their appearance. In consequence of this proliferation of the lutein-cells, the contents of the follicle are gradually pressed toward the “stigma,” the superficial pole of the follicle, and the follicle itself is pushed toward the surface until it finally comes into contact with the germinal epithelium. Meanwhile the follicular epithelium undergoes fatty degeneration, alike in the membrana granulosa and in the discus proligerus. In consequence of the proliferation of the lutein-cells, on the one hand, and the fatty degeneration of the epithelium, on the other, the follicle opens at its weakest point, the stigma, and the ovum is extruded, with the liquor folliculi, and a number of cells belonging to the follicular epithelium. (To illustrate these changes we have borrowed FIGS. 15, 16, and 17 from the monograph, by _Pfannenstiel_ on _Diseases of the Ovary_, in _J. Veits’ Handbook of Gynecology_.)
The ovaries, which in the new-born female infant are flattened, ribbon-like bodies one-half to one centimeter (0.2 to 0.4″) in length, and in childhood are cylindrical, with a perfectly smooth surface, assume at the time of puberty a more or less flattened form. During the menarche they have an elongated oval shape, flattened from side to side, their average length being 2.5 to 5.0 centimetres (1 to 2″), width 1.5 to 3.0 centimetres (0.59 to 1.18″), thickness 0.6 to 1.4 centimetres (0.24 to 0.55″), weight 5 to 8 grammes (77 to 123 grains). After the repeated occurrence of ovulation, the surface of the ovary becomes more and more uneven, being thickly covered with fossæ or scar-like fissures.
The vagina during virgin girlhood is narrow, and its mucous surface is beset with numerous rugæ, which may be plainly felt as well as seen. The calibre of the vagina is proportionately less the younger the girl. The examining finger is gripped by the vaginal wall as by an india-rubber tube (_Maschka_). The vaginal portion of the cervix is felt in the form of a truncated cone, with a smooth surface, rather dense in consistence; the external os opens at the bottom of a small depression on its surface, in the form of a short oval, the long axis of which is transversely directed. Shortly before the menarche, Bartholin’s glands become noticeable on either side of the lower end of the vagina between the sphincter muscles.