Location of the uterus in women. Interesting facts about the uterus

A woman’s uterus is an organ designed by evolution for bearing and giving birth to a child. What does a woman's uterus look like? The shape is similar to a pear or has the appearance of a truncated cone, hollow inside, and is an organ of the reproductive system. The place where the uterus is located is the central part of the female pelvic cavity, reliably protected by the pelvic bone frame, muscles, and adipose tissue for complete and reliable protection during pregnancy. The structure of a woman’s uterus is so well thought out that it is difficult to find a more protected organ.

Topography

Where is a woman's uterus located? It is located inside the pelvic cavity behind the bladder and in front of the rectum. In the place where a woman’s uterus is located, sheets of peritoneum cover its front wall up to the cervix, and the back including the cervix, which helps to divide the space into separate anatomical zones. Along the edges, two peritoneal layers unite and participate in the formation of ligaments. Topographically stands out:

The anterior surface is the part of the organ located in front of the bladder. In front of it there is a cystic tissue space filled with fatty tissue, in which lymph nodes and lymphatic ducts are located.
The posterior surface is located anterior to the rectum. Between it and the intestine, a retrouterine space is formed, filled with fiber with lymphatic collectors.
Right and left ribs of the uterus.

The adipose tissue surrounding on all sides - parametric tissue - is the place where feeding arterial vessels, veins pass, and lymph nodes and ducts can be located.

The volume of a woman's uterus is about 4.5 cubic centimeters, the average size is 7x4x3.5 cm. What a woman's uterus can look like, its shape, size, volume depends on how many births the woman has had. The organ parameters of women who have given birth and women who have not given birth differ. The uterus of a woman who has given birth weighs almost twice as much as that of a nulliparous woman. On average, the weight ranges from 50 to 70 g. In order to show how the main physiological function of this small organ is carried out, let us consider the main structural features.

Anatomical structure

The anatomy of the uterus is determined by the main physiological function of the organ. Different parts of the organ are supplied with blood differently, lymph flows into different collectors, which is important to consider during surgical interventions on the organ. This plays a key role in determining treatment tactics for pathological processes. Anatomically, there are three areas:

The body of the uterus is the largest part by volume and forms the uterine cavity. The section has a triangular truncated shape.
The fundus is an anatomical part of the organ that forms an elevation above the place where the fallopian tubes open.
The cervix is a cylindrical, up to three centimeters long, hollow tube that connects the body to the vagina.

Body

The body of the uterus is the most voluminous anatomical part of the organ; it accounts for approximately two-thirds of the total volume. It is here that the implantation of a fertilized egg, the formation of the placenta, and the growth and development of the child occur. It has the shape of a truncated cone, with the base facing upward, forming a physiological bend.

In the upper part of the body, on the right and left edges, the fallopian tubes flow into its lumen, through which the egg from the ovary enters the organ cavity.

Bottom

The uppermost part of the organ. If you mentally connect the points where the fallopian tubes open with a straight line passing through the body of the uterus, then the dome-shaped overhang of a part of the body forms the bottom. It is by the height of the bottom that the gestational age is determined.

Neck

Topographically, the place where the cervix is located in front and behind is surrounded by cellular spaces: in front - vesical, in back - rectal. The cervix is covered with a sheet of peritoneum only along its posterior surface. The structure of the cervix is determined by the physiological functions performed. This is a hollow tube that connects the uterine cavity to the vagina. It accounts for a third of the length of the entire organ. The neck has different structural parts:

Isthmus. This is a small area of physiological narrowing in the lower part of the uterine body, the place of transition to the cervical part.
The vaginal section of the cervical part directly faces the inside of the vagina and communicates with it through an opening - the external os. The vaginal part is clearly visible during a gynecological examination.
The supravaginal area is the part of the cervix facing the uterine cavity.
The cervical canal connects the vagina through the os to the uterine cavity.

The identification of various anatomical areas in a small part of the organ, which is the cervical part, is due to the peculiarities of its structure.

The structure of the walls of the organ

The structure of the uterine wall has clearly defined three layers:

External serous - it is formed by a layer of peritoneum lining the organ on the outside - the perimeter.
The middle muscle, representing several layers of muscle tissue - the myometrium.
The internal, lining organ from the inside, which is a mucous membrane, is the endometrium.

The layers of the uterus have some differences depending on the functional purpose of its individual parts.

Perimeter shell

Covers the body from the outside, is a sheet of peritoneum lining all the organs of the abdominal cavity. The perimetry is a continuation of the serous membrane of the bladder, continuing and covering the uterine surface.

Muscularis

The middle membrane, represented by muscle fibers, has a rather complex structure. Its thickness varies in different parts of the organ. In the fundus area, the muscular lining of the uterus is thickest. This is due to the need for the muscle to contract and expel the fetus during labor. The severity of the muscle layer of the fundus area is also different in the pregnant and non-pregnant uterus, reaching a thickness of four centimeters at the time of birth.

The fibers of muscle tissue have a three-dimensional direction, are tightly intertwined with each other, forming a fairly reliable frame, between the components of which elastin and connective tissue fibers are located.

The size and volume of the uterus changes over time due to changes in the thickness and size of the fibers of the muscle layer. This process is influenced by many factors, but the changing level of sex hormones at different periods of a woman’s life is of primary importance. Significantly increasing during pregnancy and childbirth, the uterus contracts again, acquiring its previous size, 6–8 weeks after the birth of the child.

Only thanks to such a complex structure of the myometrium is it possible to maintain pregnancy, pregnancy and childbirth.

Inner lining of the uterus

The endometrium is represented by a cylindrical epithelium with a large number of glands and is two-layered:

Superficially located functional layer.
The basal layer, located under the functional one.

The surface layer of the endometrium is represented by a glandular cylindrical epithelium containing a large number of glands; receptors for sex hormones are located on the surface of its cells. Capable of changing in thickness at different periods of a woman’s reproductive cycle under the influence of changing hormonal levels. It is this layer of epithelial cover that is rejected during menstrual bleeding, and implantation of a fertilized egg occurs into it.

The basal layer is a thin layer of connective tissue, tightly connected to the muscle layer, participating in the formation of a single, functionally coherent mechanism.

Features of the internal structure of the neck

The internal structure of this small part of the uterus has its own differences, due to the functional loads performed:

The cervix is covered with an outer serous membrane only at the back.
It has a thin, not very pronounced layer of smooth muscle fibers and a sufficient amount of collagen. This structure contributes to changes in the size of the canal during childbirth. Cervical dilatation during labor reaches 12 cm.
A large number of mucous glands produce a secretion that closes the lumen of the canal, which helps to perform a barrier and protective function.
The inner epithelial layer of the canal is represented by columnar epithelium, the area of the external pharynx is covered with stratified squamous epithelium. Between these parts of the cervix there is a so-called transition zone. Pathological changes in the structure of the epithelial cover of this area often occur and lead to the occurrence of dysplasia and cancer. Particular close attention to this area during an examination by a gynecologist is absolutely recommended.

Functions

The functions of the uterus in a woman’s body are difficult to overestimate. Being a barrier to the penetration of infection, it is involved in the direct regulation of hormonal conditions. The key purpose is to perform the reproductive function. Without it, the process of implantation, gestation and birth of a child is impossible. The birth of a new person, an increase in population size, and ensuring the transfer of genetic material are possible only thanks to a woman and the coordinated work of the organs of her reproductive system.

That is why the problems of preserving women’s health in all countries of the world are not only of purely medical, but also social significance.

The anatomy of the female reproductive system is quite complex and its main organ is the uterus. This organ consists of several parts, supplemented by appendages, etc. All of them perform a number of important functions, the most significant of which, from the point of view of evolution, is reproductive. This article talks about the structure of the uterus, what changes it undergoes during pregnancy and what features and pathologies it may have.

Definition

What is a uterus? This is the main part of the reproductive system. It, along with other important functional components, is the main organ necessary for conceiving and bearing a child. In this material, it is considered together with appendages, because without them it does not function. The structure and its structure, together with its appendages, are presented in the diagram in this article.

Neck

The cervix is the cervical canal. The inside is lined with endometrium and consists of elastic muscle tissue. The structure of the cervix also suggests the presence of a large number of cervical glands, which produce special cervical mucus. The length of the cervix is 3-4 cm, but changes throughout pregnancy.

This part connects the uterine cavity to the vagina. It is through the cervical canal that sperm penetrate into the cavity to fertilize the egg in it.

Body

The body of the uterus is the main part of this organ. It has a round or slightly ovoid shape, which changes during pregnancy. It consists of a cavity and the walls with which this cavity is formed. The lower (relative to its location in the body) part of the body connects to the cervix, at an obtuse angle, if the location of the cervix is normal. The fallopian tubes join the organ on both sides.

The standard dimensions for this part of the organ are as follows:

The weight of the uterus is 50-60 g, in women who have given birth - up to 80 g;
Length of the uterus – 4-7 cm;
Width – up to 4 cm;
The thickness of the uterus is 4-5 cm.

Cavity

The uterine cavity is the free space that exists inside the body of the uterus and is formed by the uterine walls. It is in it that fertilization of the egg occurs, where the placenta and embryo are subsequently formed, etc. The volume of this space is 5-6 cubic centimeters. But during pregnancy it increases significantly.

Walls

How many layers do the uterine walls have? If you look at them in cross-section, you can distinguish three functional layers:

(located inside);
(muscle layer;
Subserrous membrane (outer layer).

This structure is constant for the entire cavity, that is, it has both the posterior and anterior walls of the uterus. The walls of the uterus normally have variable thickness, depending on the stage of the menstrual cycle. They can reach 3-4 cm in thickness.

Ligaments

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A woman’s reproductive organs are designed to perform important functions and have an interesting anatomical structure. You can verify this by looking at what a woman’s uterus looks like. It shows how the most important part of the female reproductive system organs works.

What does a woman's uterus look like? Its location

The uterus is a strong muscle that is well supplied with blood and is an important part of the oviduct. This organ is pear-shaped and is located in the pelvis. The rectum is adjacent to the uterus at the back, and the bladder is located in front of it.

The weight of the organ of a nulliparous woman is 40-50 grams, while the weight of a woman who has given birth many times is 90-100 grams.

The organ consists of several parts

cervix

At the top of the body there is an expanded part, the bottom. At the bottom of the organ is the cervix and connects to the vagina.

Anatomical structure of the cervix

The cervix is a rounded septum. It is based on collagen tissues containing smooth muscle inclusions. The uterus and vagina are connected by a canal whose tissues are columnar epithelium. The canal has the ability to secrete mucous secretions. A feature of its structure is the presence of special folds that protect the organ from vaginal contents entering it.

Features of the anatomical structure of the uterus

A feature of the anatomical structure is the location of the bottom at a slight forward inclination, while the angle formed by the body and neck is directed towards the vagina.

The internal cavity of the uterus has a triangular shape; through openings it connects with the fallopian tubes, which extend from the organ in both directions. The outer (serous), middle (muscular) and inner (mucosal) layers are the constituent walls.

The outer shell is surrounded on three sides by the abdominal cavity. And the lower part is adjacent to the rectum and bladder. The uterus is fixed with the help of broad ligaments formed from fused layers of the peritoneum, as well as with the help of the pelvic day muscles and fascia. Consisting of three layers of smooth muscle, the tunica media is the most powerful.

The basis of the mucous membrane is ciliated columnar epithelium, which is nourished by a large number of glands. The uterus is supplied with blood through branches of the iliac artery, which diverge to the ovaries and fallopian tubes.

Monthly cycles, the onset of pregnancy, and gestation are the causes of various changes in the condition of the uterus.

The length of the uterus in an adult woman is on average 7-8 cm, width - 4 cm, thickness - 2-3 cm. The weight of the uterus in nulliparous women ranges from 40 to 50 g, and in those who have given birth reaches 80-90 g. The volume of the uterine cavity is 4-6 cm.

The uterus as an organ is largely mobile and, depending on the condition of neighboring organs, can occupy different positions. Normally, the longitudinal axis of the uterus is oriented along the axis of the pelvis. Most of the surface of the uterus is covered by the peritoneum, with the exception of the vaginal part of the cervix. The uterus is pear-shaped and flattened in the anteroposterior direction.

Anatomy

Parts of the uterus

The uterus consists of the following parts:

Fundus of the uterus- This is the upper convex part of the uterus, protruding above the line where the fallopian tubes enter the uterus.
Body of the uterus- The middle (larger) part of the organ has a cone-shaped shape.
Cervix- The lower narrowed rounded part of the uterus.

Functions

The uterus is the organ in which embryo development and gestation occur. Due to the high elasticity of the walls, the uterus can increase in volume several times during pregnancy. Being an organ with developed muscles, the uterus actively participates in the expulsion of the fetus during childbirth.

Pathologies

Developmental anomalies

Aplasia (agenesis) of the uterus- extremely rarely, the uterus may be completely absent. There may be a small infantile uterus, usually with a pronounced anterior incursion.
Duplication of the uterine body- a defect in the development of the uterus, which is characterized by duplication of the uterus or its body, which occurs as a result of incomplete fusion of the two Müllerian ducts at the stage of early embryonic development. As a result, a woman with a double uterus may have one or two cervixes and one vagina. With complete nonfusion of these ducts, two uteruses with two cervixes and two vaginas develop.
Intrauterine septum- incomplete fusion of the embryonic rudiments of the uterus in various variants, can lead to the presence of a septum in the uterus - a “bicornuate” uterus with a clearly visible sagittal depression at the bottom or a “saddle-shaped” uterus without a septum in the cavity, but with a notch at the bottom. With a bicornuate uterus, one of the horns may be very small, rudimentary, and sometimes unlaced.

Diseases

Prolapse and prolapse of the uterus- Prolapse of the uterus or a change in its position in the pelvic cavity and its displacement down the inguinal canal is called complete or partial uterine prolapse. In rare cases, the uterus slips directly into the vagina. In mild cases of uterine prolapse, the cervix protrudes forward at the bottom of the genital opening. In some cases, the cervix prolapses into the genital slit, and in particularly severe cases, the entire uterus prolapses. Uterine prolapse is described based on how much of the uterus protrudes. Patients often complain of the sensation of a foreign body in the genital fissure. Treatment can be either conservative or surgical, depending on the specific case.
Uterine fibroids- A benign tumor that develops in the muscular lining of the uterus. Consists mainly of elements of muscle tissue, and partly of connective tissue, also called fibromyoma.

Uterine polyps- Pathological proliferation of the glandular epithelium, endometrium or endocervix against the background of a chronic inflammatory process. Hormonal disorders play a role in the genesis of polyps, especially uterine ones.

Uterine cancer- Malignant neoplasms in the uterine area.
- Cancer of the uterus- Uterine cancer refers to endometrial cancer (the lining of the uterus) that spreads to the walls of the uterus.
- Cervical cancer- a malignant tumor, localized in the cervix area.

Endometritis- Inflammation of the uterine mucosa. In this case, the disease affects the functional and basal layers of the uterine mucosa. When it is accompanied by inflammation of the muscular layer of the uterus, they speak of endomyometritis.

Cervical erosion- This is a defect in the epithelial lining of the vaginal part of the cervix. There are true and false erosions of the cervix:
- True erosion- refers to acute inflammatory diseases of the female genital organs and is a frequent companion to cervicitis and vaginitis. It usually occurs against the background of general inflammation in the cervix, caused by sexually transmitted infections or conditionally pathogenic vaginal flora, under the influence of mechanical factors, malnutrition of the cervical tissue, menstrual cycle disorders, and hormonal imbalance.
- Ectopia (pseudo-erosion)- there is a common misconception that ectopia is the body’s response to the appearance of erosion, since the body is trying to replace a defect in the mucous membrane of the vaginal (outer) part of the cervix with columnar epithelium lining the uterine (inner) part of the cervical canal. Often this confusion arises due to the outdated point of view of some doctors. In fact, ectopia is an independent disease that has little to do with true erosion. The following types of pseudo-erosions are distinguished:
  - Congenital ectopia- in which the cylindrical epithelium can be located outside the external os of the cervix in newborns or move there during puberty.
  - Acquired ectopia- cervical ruptures during abortion lead to deformation of the cervical canal, resulting in post-traumatic ectopia of the columnar epithelium (ectopion). Often (but not always) accompanied by an inflammatory process.

Diagnostics

Operations

Abortion(not to be confused with the term “spontaneous abortion”, meaning “miscarriage”) - an operation aimed at terminating a pregnancy, performed in its first 12 weeks in a hospital setting at the request of the woman. It is a mechanical destruction of the embryo with further curettage of the uterine cavity. There are clinical (in a hospital setting) and criminal abortions. Any abortion can lead to serious complications. Criminal abortion can cause a woman's death.
Vacuum aspiration or the so-called “mini-abortion” - an intervention aimed at terminating a pregnancy at an extremely early stage - from twenty to twenty-five days without expected menstruation. Refers to minimally invasive operations and can be performed on an outpatient basis.
C-section(Latin caesarea “royal” and sectio “incision”) - carrying out childbirth using abdominal surgery, in which the newborn is removed not through the natural birth canal, but through an incision in the abdominal wall of the uterus. Previously, a caesarean section was performed only for medical reasons, but now, increasingly, the operation is performed at the request of the woman in labor.
Hysterectomy- (Greek hystera uterus + Greek ectome ectomy, removal; possibly spelled hysterectomy; another common name is hysterectomy) - a gynecological operation in which a woman’s uterus is removed.

Links

BSE.sci-lib.com. - The meaning of the word “Uterus” in the Great Soviet Encyclopedia. Retrieved September 2, 2008.

The uterus (uterus; metra; hystera) is a smooth muscle hollow organ that provides menstrual and reproductive functions in the female body. The shape resembles a pear, compressed in the anteroposterior direction. The weight of a virgin uterus that has reached full development is about 50 g, length 7–8 cm, greatest width (at the bottom) - 5 cm, walls are 1–2 cm thick. The uterus is located in the pelvic cavity between the bladder and rectum.

Anatomically, the uterus is divided into the fundus, body and cervix (Fig. 6--4).

Rice. 6-4. Frontal section of the uterus (diagram).

The fundus uteri is the upper part protruding above the line of entry into the uterus of the fallopian tubes. The body (corpus uteri) has a triangular outline, which gradually narrows towards a rounder and narrower neck (cervix uteri), which is a continuation of the body and makes up about a third of the entire length of the organ. With its outer end, the cervix protrudes into the upper part of the vagina (portio vaginalis cervicis). Its upper segment, adjacent directly to the body, is called the supravaginal part (portio supravaginalis cervicis), the anterior and posterior parts are separated from each other by edges (margo uteri dexter et sinister). In a nulliparous woman, the shape of the vaginal part of the cervix approaches the shape of a truncated cone, while in a woman who has given birth, it has a cylindrical shape.

The part of the cervix visible in the vagina is covered with stratified squamous non-keratinizing epithelium. The transition between the glandular epithelium lining the cervical canal and the squamous epithelium is called the transformation zone. It is usually located in the cervical canal, just above the external os. The transformation zone is clinically extremely important, since it is here that dysplastic processes that can transform into cancer often arise.

The uterine cavity in the frontal section has the shape of a triangle, the base of which faces the bottom. The tubes (ostium uterinum tubae uterinae) open into the corners of the triangle, and the apex continues into the cervical canal, helping to retain the mucus plug in its lumen - the secretion of the glands of the cervical canal. This mucus has extremely high bactericidal properties and prevents the penetration of infectious agents into the uterine cavity. The cervical canal opens into the uterine cavity with the internal os (orificium internum uteri), into the vagina - with the external os (orificium externum uteri), which is limited by two lips (labium anterius et posterius).

In nulliparous women, it has a point shape, in women who have given birth, it has the shape of a transverse slit. The transition point of the uterine body to the cervix outside of pregnancy is narrowed to 1 cm and is called the isthmus of the uterus (isthmus uteri), from which in the third trimester of pregnancy the lower uterine segment is formed - the thinnest part of the uterine wall during childbirth. This is where uterine rupture most often occurs; in this same area, the uterus is incised during CS surgery.

The wall of the uterus consists of three layers: the outer - serous (perimetrium; tunica serosa), the middle - muscular (myometrium; tunica muscularis), which makes up the main part of the wall, and the inner - mucous membrane (endometrium; tunica mucosa). In practical terms, one should distinguish between perimetrium and parametrium - peri-uterine fatty tissue lying on the anterior surface and sides of the cervix, between the leaves of the broad ligament of the uterus, in which blood vessels pass. The uniqueness of the uterus as an organ capable of bearing pregnancy is ensured by the special structure of the muscle layer. It consists of smooth muscle fibers intertwined with each other in different directions (Fig. 6-5) and having special gap junctions (nexuses), which allows it to stretch as the fetus grows, maintaining the necessary tone, and function as a large coordinated muscle mass (functional syncytium).

Rice. 6-5. Location of the muscular layers of the uterus (diagram): 1 - fallopian tube; 2 - own ligament of the ovary; 3 - round ligament of the uterus; 4 - sacrouterine ligament; 5 - cardinal ligament of the uterus; 6 - vaginal wall.

The degree of contractility of the uterine muscle largely depends on the concentration and ratio of sex hormones, which determine the receptor sensitivity of muscle fibers to uterotonic effects.

The contractility of the internal os and isthmus of the uterus also plays a certain role.

The mucous membrane of the uterine body is covered with ciliated epithelium, has no folds and consists of two layers with different purposes. The superficial (functional) layer is rejected at the end of the infertile menstrual cycle, which is accompanied by menstrual bleeding. When pregnancy occurs, it undergoes decidual transformations and “receives” the fertilized egg. The second, deeper (basal) layer serves as a source of regeneration and formation of the endometrium after its rejection. The endometrium is equipped with simple tubular glands (glandulae uterinae), which penetrate to the muscle layer; in the thicker mucous membrane of the cervix, in addition to the tubular glands, there are mucous glands (glandulae cervicales).

The uterus has significant mobility and is located in such a way that its longitudinal axis is approximately parallel to the axis of the pelvis. The normal position of the uterus with an empty bladder is anterior tilt (anteversio uteri) with the formation of an obtuse angle between the body and the cervix (anteflexio uteri). When the bladder is distended, the uterus may be tilted back (retroversio uteri). A sharp, constant posterior bend of the uterus is a pathological phenomenon (Fig. 6--6).

Rice. 6-6. Variants of the position of the uterus in the pelvic cavity: a, 1 - normal position anteflexsio versio; a, 2 - hyperretroflexio versio; a, 3 - anteversio; a, 4 - hyperanteflexio versio; b - three degrees of uterine retrodeviation: b, 1 - 1st degree; b, 2 - 2nd degree; b, 3 - 3rd degree; 4 - normal position; 5 - rectum.

The peritoneum covers the uterus from the front to the junction of the body with the cervix, where the serosa folds over the bladder. The depression of the peritoneum between the bladder and the uterus is called the vesicouterine (excavatio vesicouterina). The anterior surface of the cervix is connected to the posterior surface of the bladder through loose fiber. From the posterior surface of the uterus, the peritoneum continues for a short distance to the posterior wall of the vagina, from where it bends onto the rectum. The deep peritoneal pouch between the rectum at the back and the uterus and vagina at the front is called the rectouterine recess (excavatio rectouterina). The entrance to this pocket is limited from the sides by folds of the peritoneum (plicae rectouterinae), extending from the posterior surface of the cervix to the lateral surfaces of the rectum. In the thickness of the folds, in addition to connective tissue, there are bundles of smooth muscle fibers (mm. rectouterini) and lig. sacrouterinum.

The uterus receives arterial blood from a. uterina and partly from a. ovarica. A. uterina, feeding the uterus, broad uterine ligament, ovaries and vagina, goes down and medially at the base of the broad uterine ligament, at the level of the internal pharynx, intersects with the ureter and, giving off to the cervix and vagina a. vaginalis, turns upward and rises to the upper corner of the uterus. It should be remembered that the uterine artery always passes over the ureter (“water always flows under the bridge”), which is important when performing any surgical interventions in the pelvic area affecting the uterus and its blood supply. The artery is located at the lateral edge of the uterus and in women who have given birth is characterized by tortuosity. Along the way, she gives branches to the body of the uterus. Having reached the fundus of the uterus, a. The uterina is divided into two terminal branches: ramus tubarius (to the tube) and ramus ovaricus (to the ovary). The branches of the uterine artery anastomose in the thickness of the uterus with the same branches of the opposite side, forming rich branches in the myometrium and endometrium, which especially develop during pregnancy.

The venous system of the uterus is formed by the plexus venosus uterinus, located on the side of the uterus in the medial part of the broad ligament. Blood flows out of it in three directions: into v. ovarica (from the ovary, tube and upper uterus), in vv. uterinae (from the lower half of the uterine body and the upper part of the cervix) and directly into v. iliaca interna - from the lower part of the cervix and vagina. The plexus venosus uterinus anastomoses with the veins of the bladder and the plexus venosus restalis. Unlike the veins of the shoulder and leg, the uterine veins do not have a surrounding and supporting fascial sheath. During pregnancy, they expand significantly and can function as reservoirs that receive placental blood during uterine contractions.

The efferent lymphatic vessels of the uterus go in two directions: from the fundus of the uterus along the tubes to the ovaries and further to the lumbar nodes and from the body and cervix in the thickness of the broad ligament, along the blood vessels to the internal (from the cervix) and external iliac (from the cervix and body ) nodes. Lymph from the uterus can also flow into the nodi lymphatici sacrales and into the inguinal nodes along the round uterine ligament.

The innervation of the uterus is extremely rich due to the participation of the autonomic and central nervous systems (CNS).

According to modern concepts, pain emanating from the body of the uterus, in combination with uterine contractions, is ischemic in origin, they are transmitted through sympathetic fibers that form the plexus hypogastricus inferior. Parasympathetic innervation is carried out by nn. splanchnici pelvici. From these two plexuses in the cervical region, the plexus uterovaginalis is formed. Noradrenergic nerves in the non-pregnant uterus are distributed mainly in the cervix and lower uterine body, as a result of which the autonomic nervous system can cause contraction of the isthmus and lower part of the uterus in the luteal phase, promoting implantation of the fertilized egg in the uterine fundus.

The ligamentous (suspensory) apparatus (Fig. 6-- 8) is directly related to the internal genital organs, ensuring the preservation of their anatomical and topographic constancy in the pelvic cavity.

Rice. 6-8. Suspension apparatus of the uterus: 1 - vesica urinaria; 2 - corpus uteri; 3 - mesovarium; 4 - ovarium; 5 - lig. suspensorium ovarii; 6 - aorta abdominalis; 7 - promontorium; 8 - colon sigmoideum; 9 - excavatio rectouterina; 10 - cervix uteri; 11 - tuba uterina; 12 - lig. ovarii proprium; 13 - lig. latum uteri; 14 - lig. teres uteri.

Along the lateral edges of the uterus, the peritoneum from the anterior and posterior surfaces passes to the lateral walls of the pelvis in the form of wide ligaments of the uterus (ligg. lata uteri), which in relation to the uterus (below the mesosalpinx) represent its mesentery (mesometrium). On the anterior and posterior surfaces of the broad ligaments, roller-like elevations from the ligas passing here are noticeable. ovarii proprium and round uterine ligaments (lig. teres uteri), which arise from the upper corners of the uterus, immediately anterior to the tubes, one on each side, and are directed forward, laterally and upward to the deep ring of the inguinal canal. Having passed through the inguinal canal, the round ligaments reach the pubic symphysis, and their fibers are lost in the connective tissue of the pubis and the labia majora of the same side.

The uterosacral ligaments (ligg. sacrouterina) are located extraperitoneally and are represented by smooth muscle and fibrous fibers that run from the pelvic fascia to the cervix and are then woven into the body of the uterus. Starting from its posterior surface, below the internal pharynx, they arc around the rectum, merging with the rectal-uterine muscles, and ending on the inner surface of the sacrum, where they merge with the pelvic fascia.

Cardinal ligaments (ligg. cardinalia) connect the uterus at the level of its cervix with the side walls of the pelvis. Damage to the cardinal and uterosacral ligaments, which provide significant support to the pelvic floor, including their stretching during pregnancy and childbirth, can cause the further development of genital prolapse (Fig. 6--9).

Rice. 6-9. Fixing apparatus of the uterus: 1 - spatium praevesicale; 2 - spatium paravesicale; 3 - spatium vesicovaginale; 4 - m. levator ani; 5 - spatium retrovaginale; 6 - spatium pararectale; 7 - spatium retrorectale; 8 - fascia propria recti; 9 - lig. sacrouterinum; 10 - lig. cardinal; 11 - lig. vesicouterina; 12 - fascia vesicae; 13 - lig. pubovesicale.