The Female Genital Organs

The female genital organs consist of an internal and an external group. The internal organs are situated within the pelvis, and consist of the ovaries, the uterine tubes, the uterus, and the vagina. The external organs are placed below the urogenital diaphragm and below and in front of the pubic arch. They comprise the mons pubis, the labia majora et minora pudendi, the clitoris, the bulbus vestibuli, and the greater vestibular glands.

The ovaries are homologous with the testes in the male. They are two nodular bodies, situated one on either side of the uterus in relation to the lateral wall of the pelvis, and attached to the back of the broad ligament of the uterus, behind and below the uterine tubes .The ovaries are of a grayish-pink color, and present either a smooth or a puckered uneven surface. They are each about 4 cm. in length, 2 cm. in width, and about 8 mm. in thickness, and weigh from 2 to 3.5 gm. Each ovary presents a lateral and a medial surface, an upper or tubal and a lower or uterine extremity, and an anterior or mesovarion and a posterior free border. It lies in a shallow depression, named the ovarian fossa, on the lateral wall of the pelvis; this fossa is bounded above by the external iliac vessels, in front by the obliterated umbilical artery, and behind by the ureter. The exact position of the ovary has been the subject of considerable difference of opinion, and the description here given applies to the ovary of the nulliparous woman. The ovary becomes displaced during the first pregnancy, and probably never again returns to its original position. In the erect posture the long axis of the ovary is vertical. The tubal extremity is near the external iliac vein; to it are attached the ovarian fimbria of the uterine tube and a fold of peritoneum, the suspensory ligament of the ovary, which is directed upward over the iliac vessels and contains the ovarian vessels. The uterine end is directed downward toward the pelvic floor, it is usually narrower than the tubal, and is attached to the lateral angle of the uterus, immediately behind the uterine tube, by a rounded cord termed the ligament of the ovary, which lies within the broad ligament and contains some non-striped, muscular fibers. The lateral surface is in contact with the parietal peritoneum, which lines the ovarian fossa; the medial surface is to a large extent covered by the fimbriated extremity of the uterine tube. The mesovarian border is straight and is directed toward the obliterated umbilical artery, and is attached to the back of the broad ligament by a short fold named the mesovarium. Between the two layers of this fold the bloodvessels and nerves pass to reach the hilum of the ovary. The free border is convex, and is directed toward the ureter. The uterine tube arches over the ovary, running upward in relation to its mesovarian border, then curving over its tubal pole, and finally passing downward on its free border and medial surface.

Structure—The surface of the ovary is covered by a layer of columnar cells which constitutes the germinal epithelium of Waldeyer. This epithelium gives to the ovary a dull gray color as compared with the shining smoothness of the peritoneum; and the transition between the squamous epithelium of the peritoneum and the columnar cells which cover the ovary is usually marked by a line around the anterior border of the ovary. The ovary consists of a number of vesicular ovarian follicles imbedded in the meshes of a stroma or frame-work.
The stroma is a peculiar soft tissue, abundantly supplied with bloodvessels, consisting for the most part of spindle-shaped cells with a small amount of ordinary connective tissue. These cells have been regarded by some anatomists as unstriped muscle cells, which, indeed, they most resemble; by others as connective-tissue cells. On the surface of the organ this tissue is much condensed, and forms a layer (tunica albuginea) composed of short connective-tissue fibers, with fusiform cells between them. The stroma of the ovary may contain interstitial cells resembling those of the testis.
Vesicular Ovarian Follicles (Graafian follicles).—Upon making a section of an ovary, numerous round transparent vesicles of various sizes are to be seen; they are the follicles, or ovisacs containing the ova. Immediately beneath the superficial covering is a layer of stroma, in which are a large number of minute vesicles, of uniform size, about 0.25 mm. in diameter. These are the follicles in their earliest condition, and the layer where they are found has been termed the cortical layer. They are especially numerous in the ovary of the young child. After puberty, and during the whole of the child-bearing period, large and mature, or almost mature follicles are also found in the cortical layer in small numbers, and also “corpora lutea,” the remains of follicles which have burst and are undergoing atrophy and absorption. Beneath this superficial stratum, other large and more or less mature follicles are found imbedded in the ovarian stroma. These increase in size as they recede from the surface toward a highly vascular stroma in the center of the organ, termed the medullary substance (zona vasculosa of Waldeyer). This stroma forms the tissue of the hilum by which the ovary is attached, and through which the bloodvessels enter: it does not contain any follicles.

Discharge of the Ovum.—The follicles, after attaining a certain stage of development, gradually approach the surface of the ovary and burst; the ovum and fluid contents of the follicle are liberated on the exterior of the ovary, and carried into the uterine tube by currents set up by the movements of the cilia covering the mucous membrane of the fimbriæ.

Corpus Luteum.—After the discharge of the ovum the lining of the follicle is thrown into folds, and vascular processes grow inward from the surrounding tissue. In this way the space is filled up and the corpus luteum formed. It consists at first of a radial arrangement of yellow cells with bloodvessels and lymphatic spaces, and later it merges with the surrounding stroma.

The uterine tubes convey the ova from the ovaries to the cavity of the uterus. They are two in number, one on either side, situated in the upper margin of the broad ligament, and extending from the superior angle of the uterus to the side of the pelvis. Each tube is about 10 cm. long, and is described as consisting of three portions: (1) the isthmus, or medial constricted third; (2) the ampulla, or intermediate dilated portion, which curves over the ovary; and (3) the infundibulum with its abdominal ostium, surrounded by fimbriæ, one of which, the ovarian fimbria is attached to the ovary. The uterine tube is directed lateralward as far as the uterine pole of the ovary, and then ascends along the mesovarian border of the ovary to the tubal pole, over which it arches; finally it turns downward and ends in relation to the free border and medial surface of the ovary. The uterine opening is minute, and will only admit a fine bristle; the abdominal opening is somewhat larger. In connection with the fimbriæ of the uterine tube, or with the broad ligament close to them, there are frequently one or more small pedunculated vesicles. These are termed the appendices vesiculosæ.

The uterus is a hollow, thick-walled, muscular organ situated deeply in the pelvic cavity between the bladder and rectum.

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.

The vagina extends from the vestibule to the uterus, and is situated behind the bladder and in front of the rectum.Its is a female sexual organ.

The external genital organs of the female are: the mons pubis, the labia majora et minora pudendi, the clitoris, the vestibule of the vagina, the bulb of the vestibule, and the greater vestibular glands.

The Mons Pubis (commissura labiorum anterior; mons Veneris), the rounded eminence in front of the pubic symphysis, is formed by a collection of fatty tissue beneath the integument. It becomes covered with hair at the time of puberty.
The Labia Majora (labia majora pudendi) are two prominent longitudinal cutaneous folds which extend downward and backward from the mons pubis and form the lateral boundaries of a fissure or cleft, the pudendal cleft or rima, into which the vagina and urethra open. The Labia Minora (labia minora pudendi; nymphæ) are two small cutaneous folds, situated between the labia majora, and extending from the clitoris obliquely downward,lateralward, and backward for about 4 cm. on either side of the orifice of the vagina, between which and the labia majora they end.

The Clitoris is an erectile structure, homologous with the penis. It is situated beneath the anterior labial commissure, partially hidden between the anterior ends of the labia minora. It consists of two corpora cavernosa, composed of erectile tissue enclosed in a dense layer of fibrous membrane, united together along their medial surfaces by an incomplete fibrous pectiniform septum; each corpus is connected to the rami of the pubis and ischium by a crus; the free extremity (glans clitoridis) is a small rounded tubercle, consisting of spongy erectile tissue, and highly sensitive. The clitoris is provided like the penis, with a suspensory ligament, and with two small muscles, the Ischiocavernosi, which are inserted into the crura of the clitoris.

The hymen is a thin fold of mucous membrane situated at the orifice of the vagina; the inner edges of the fold are normally in contact with each other, and the vaginal orifice appears as a cleft between them. The hymen varies much in shape