The nerves of the uterus and its connecting structures of the generative system, are derived, either directly or indirectly, from all three of the great nervous centres of the body; and by their union and concentration serve to render the sexual system of the female the great physiological centre of her entire organism. The nerves which are distributed to the uterus are, in part, derived from the great sympathetic, and partly from the spinal nervous system. But these latter, as branches of the third and fourth sacral nerves, given off from the cerebro-spinal axis, are, indirectly at least, derived also from the cerebral nervous centre, as well as from the spinal; although they are not under the immediate control of the will.
The nerves which are distributed to the uterus from the sympathetic system, are derived from the aortic, and from the hypogastric plexus. The former, -variously named, as the renal, the spermatic or ovarian plexuses, according to their more immediate relations are all derived from the great solar or epigastric plexus; and are intimately connected with all the other pelvic, abdominal and thoracic nervous centres. Hence the powerful sympathy which exists between the womb itself and all the other great organs of the female. Hence, too the intense pain felt at the pit of the stomach in cases of uterine neuralgia; and the nausea and vomiting which are so often associated with peculiar conditions of the impregnated womb.
The nerves which are distributed to the uterus from the hypogastric plexus, come directly from the pelvic portion of the sympathetic; and have associated with themselves the filaments from the third and fourth sacral nerves, which connect the womb with the general muscular apparatus of the body. The former class of nerves having especial relation to the two great functions of nutrition and reproduction, as in the growth of the womb itself, and of the ovum which it may contain in the impregnated state:- the latter having relation to those muscular powers of the womb by which it is enabled to exert itself so wonderfully to expel the product of conception at full term, and to combine with its own efforts the muscular powers of all other parts of the body.
Unlike other muscular structures, the nervous filaments penetrate into the substance of the womb; and during the period of uterogestation all the uterine nerves are very greatly enlarged.
The virgin uterus is situated in the centre of the pelvis, just above the vagina, between the bladder in front and the rectum behind. In connection with the vagina, it describes a curve similar to that of the general axis of the pelvis. Thus it appears supported or suspended in the midst of the pelvis; and in this position it is sustained by ligaments, which are processes given off from its own substance, or from the enveloping peritoneal membrane. These are arranged in four pairs, and are known as the anterior, the posterior, the round and the broad ligaments. In addition to these, which serve rather to steady the womb in its position, the peritoneum itself appears to afford the principal direct support to the uterus.
The anterior ligaments (vesico-uterine) are two semilunar of falciform processes of the peritoneal tunic of the uterus, which connect the cervix with the posterior surface of the bladder.
The posterior ligaments (recto-uterine) are two similar elongations of the same membrane, by which the sides of the uterus are connected with the rectum.
The round ligaments, continuous with the proper tissue of the womb, are produced from the anterior and superior part of its body. They are four or five inches long, situated between the layers of the broad ligament, and attached to the superior angles of the uterus, one on each side a little in front of the Fallopian tube (Fig. 14 G.) From this point the ligament proceeds outward and forward to pass through the inguinal canal towards the symphysis pubis where its expanded fibres are distributed to the subcutaneous cellular tissue of the groin, mons veneris and dartoid pouch of the labia. The tubular process in this ligament, called the canal of Nuck, is analogous to the peritoneal pouch which accompanies the descent of the testes in the male.
The broad, or lateral ligaments are formed by the union and prolongation of the peritoneum from the anterior and posterior faces of the uterus; and they extend laterally from the sides of the uterus to those of the pelvis. By this partition wall, or septum, cavity of the pelvis is divided into an anterior portion, containing the bladder, urethra and vagina, and a posterior portion, containing the rectum. By reference to Fig. 14, it will be apparent that this double membrane envelopes, on either side, superiorly the Fallopian tube, mediately the ovary, and inferiorly and anteriorly the round ligament, already described.
THE FALLOPIAN TUBES. – The first of the ovarian appendages of the uterus consists of the Fallopian tubes, one on each side; through which the ovary is transmitted to the womb. These exceedingly minute canals lead out from the cavity of the uterus, at its superior, lateral angle, and terminate at about four inches in distance, in free, fringed borders, or fimbriated extremities. Their interior surface is continuous with the mucous lining membrane of the womb; and their external covering is composed of a prolongation of its peritoneal coat. Between this mucous lining membrane and the peritoneal tunic, is interposed a middle membrane, probably of cellular tissue, which is capable of producing the peristaltic action of these tubes, by means of which the ova are transmitted to the uterus. This peristaltic action is always from the ovary, towards the uterus.
The internal orifice of the Fallopian tube, called the ostium internum, or uterinum, is so small as scarcely to admit the introduction of a fine bristle. From this orifice, the tube widens till it is finally developed into a trumpet shaped extremity, the pavilion. At the base of the pavilion a contracted circle, the ostium abdominale, forms the termination of the tube; and from this circle radiate the fringes which compose the pavilion, or fimbriated extremity itself. The ovules discharged at the menstrual periods, pass through the Fallopian tubes to the uterus. The seminal aura of the male, is conveyed to the ovaries through the ovarian ligaments and fecundation results. The reflex irritation of the ovum breaking through the ovary, causes the fimbriated extremity to apply itself to the ovary. The ovule thus impregnated is transmitted to the womb, in a manner not different from that in which the unimpregnated ova are conveyed.
THE OVARIES.- The ovaries are the analogues in the female of the testes in the male. They are two in number, situated, one on each side of the uterus, in the posterior part of the broad ligaments behind and below the Fallopian tubes. They are sustained in their proper position by these broad ligaments, to which they are attached by their anterior margins; and by their own ovarian ligaments, Fig. 14 H.H. which connect them with the uterus. In shape, the ovaries are oval, elongated and flattened from above downwards. Each ovary is about an inch and a half in length; three -quarters of an inch in width, and about a third of an inch thick. But they vary in size in different conditions of the system; increasing in volume at puberty,
Fig. 18
Ovary of the Young Female after Puberty.
A. Body of the Ovary. B. Utero-ovarian ligament. C. Tubo-ovarian ligament. D. Fallopian tube. E. Fimbriated extremity of the tube.
especially at the monthly periods,-and in most instances become more or less atrophied after the final cessation of the menses.
Beneath the peritoneal coat which invests the ovary externally, appears the tunica albuginea, the proper fibrous coverings of the organ. This fibrous coat, which is dense and firm in structure, encloses the fibrous, spongy, vascular tissue, or stroma, peculiar to the ovary. In this stroma or matrix, are found embedded in various stages of development, the Graafian vesicles ovarian, vesicles or ovisacs, containing the ova or ovules. In the adult female, fifteen or twenty of these vesicles may be distinguished already formed; and a much larger number of very minute vesicular germs in course of development.
