The document discusses the structure of the uterus. It begins by reviewing the location of the uterus in the pelvis and its parts including the fundus, body, and cervix. It then describes the shape, size, and layers of the uterus including the perimetrium, myometrium, and endometrium. Finally, it discusses the blood supply, lymph drainage, nerve supply, and supporting ligaments and muscles of the uterus.
3. STRUCTURE OF UTERUS.
BY: MS. GINI BIJI
F. Y. M.SC. NURSING STUDENT
S.V.B.C.O.N. – SILVASSA
LECTURE METHOD PRACTICE.
4. OBJECTIVE OF THIS LECTURE:
At the end of my lecture the students will be able to:
1. Review the synonym of uterus and its location.
2. Elaborate the position of uterus.
3. Discuss on the measurement of uterus.
4. Enumerate the parts of uterus.
5. Locate the structure of uterus.
5. INTRODUCTION:
Synonym: Latin - Uterus, Greek – Hystera.
Commonly known also as Womb.
The uterus is a childbearing organ in females.
The uterus is a thick-walled, muscular organ with
narrow lumen.
Situated in the pelvis between the urinary bladder
and the rectum.
Superiorly, on each side, it communicates with the
uterine tube and inferiorly with the vagina.
6. POSITION:
It is flattened anteroposteriorly.
In most women, it leans forward (anteversion), and is
bent forward (anteflexion), almost at right angles to
vagina.
When the body is upright, the uterus lies in an almost
horizontal position.
The parts of the uterus are the fundus, body and the
cervix.
7. SHAPE AND SIZE:
It is pear-shaped, being flattened
anteroposteriorly.
Measurements:
Length : 7.5 cm.
Breadth at fundus : 5 cm.
Thickness : 2.5 cm.
Weight : 30–40 g.
Volume: of non pregnant uterus is 10-20 ml
whereas of pregnant uterus is 5 liters.
8. PARTS OF THE UTERUS:
The uterus is divided into three parts:
Fundus: This is the dome- shaped part of the
uterus above the openings of the uterine
tubes.
Body: This is the main part. It is narrowest
inferiorly at the internal os where it is
continuous with the cervix.
Cervix(‘neck’ of the uterus): This protrudes
through the anterior wall of the vagina,
opening into it at the external os.
9. CONT…
The body forms upper 2/3rd of uterus and
cervix forms the lower 1/3rd of the uterus.
The junction between the body and cervix is
marked by a circular constriction called
isthmus.
The uterine tubes are attached to the upper
part of the body.
The point of fusion between the uterine tube
and body is called cornu of the uterus.
10. BODY:
Above the imaginary horizontal plane passing through the
openings of the uterine tubes, expanded dome-like end of
the body is called fundus.
The fundus is convex on all sides and covered by the
peritoneum.
The body extends from the fundus to the isthmus and
contains the uterine cavity.
11. CERVIX:
It is the lower cylindrical part.
Its lower part projects into the upper part of the
vagina through its anterior wall.
Thus, the cervix is divided into two parts:
(a) upper supravaginal part. (b) lower vaginal part.
Cervical wall made of outer stroma-connective
tissue containing collagen; only 10-15% smooth
muscle.
Secretions- alkaline, thick ,scanty-rich in
mucoprotein, fructose, NaCl.
12. STRUCTURE:
The walls of the uterus are composed of 3 layers of tissue:
Perimetrium, Myometrium And Endometrium.
1.PERIMETRIUM: this is peritoneum, which is distributed
differently on the various surfaces of the uterus.
Anteriorly, it lies over the fundus and the body where it is
folded on to the upper surface of the urinary bladder. This
fold of peritoneum forms the vesicouterine pouch.
Posteriorly, the peritoneum covers the fundus, the body
and the cervix, then it folds back on the rectum to form the
rectouterine pouch of Douglas.
13. Laterally, only the fundus is
covered because the
forms a double fold with the
uterine tubes in the upper free
border.
This double fold is the broad
ligament, which, at its lateral
ends, attaches the uterus to the
sides of the pelvis.
14. CONT…
2.MYOMETRIUM: This is the thickest layer
of tissue in the uterine wall. It is a mass of
smooth muscle fibers interlaced with
areolar tissue, blood vessels and nerves.
3. ENDOMETRIUM: This consists of
columnar epithelium containing a large
number of mucus- secreting tubular glands.
It is divided functionally into two layers:
1. Functional layer
2. Basal layer
15. The functional layer is the upper layer and it
thickens and becomes rich in blood vessels
in the first half of the menstrual cycle. If the
ovum is not fertilised and does not implant,
this layer is shed during menstruation.
The basal layer lies next to the myometrium,
and is not lost during menstruation. It is the
layer from which the fresh functional layer is
regenerated during each cycle.
16. BLOOD SUPPLY, LYMPH DRAINAGE AND NERVE SUPPLY:
Arterial supply : This is by the uterine
arteries, branches of the internal iliac
arteries. They pass up the lateral aspects
of the uterus between the 2 layers of the
broad ligaments. They supply the uterus
and uterine tubes and join with the
ovarian arteries to supply the ovaries.
Venous drainage : The veins follow the
same route as the arteries and eventually
drain into the internal iliac veins.
17. CONT..
Lymph drainage : Deep and
superficial lymph vessels drain
lymph from the uterus and the
uterine tubes to the aoric lymph
nodes and groups of nodes
associated with the iliac blood
vessels.
Nerve supply : The sympathetic
supply is from T12 and L1
segments. The parasympathetic
supply is from pelvic splanchnic
nerves (sacral 2, 3,4 segments).
18. SUPPORTING STRUCTURES:
The uterus is supported in the pelvic cavity
by surrounding organs, muscles of the pelvic
floor and ligaments that suspend it from the
walls of the pelvis.
Broad ligaments : Theses are formed by a
double fold of peritoneum, one on each side
of the uterus. They hang down from the
uterine tubes as though draped over them
and at their lateral ends they are attached to
the sides of the pelvis.
Blood and lymph vessels and nerves pass to
the uterus and uterine tubes between the
layers of the broad ligaments.
20. CONT..
Round ligaments : These are bands of
fibrous tissue between the 2 layers of
broad ligament, one on each side of the
uterus. They pass to the sides of the
pelvis then through the inguinal canal to
the end by fusing with the labia majora.
Uterosacral ligaments : These originate
from the posterior walls of the cervix and
vagina and extend backwards, one on
each side of the rectum, to the sacrum.
21. CONT…
Transverse cervical (cardinal)
ligaments : These extend one from each
side of the cervix and vagina to the side
walls of the pelvis.
Pubocervical fascia : This extends
forward from the transverse cervical
ligaments on each side of the bladder
and is attached to the posterior surface
of the pubic bones.
22. OTHER SUPPORTS:
The levator ani of both sides from
pelvic diaphragm which is the main
support, especially the
pubovaginalis fibres of levator ani.
Other muscles also help.
Perineal body provides anchor for
action of pelvic diaphragm.
25. BIBLIOGRAPHY:
1. Ashalata N Nandedkar, Textbook of Anatomy and Physiology for
Nursing and Healthcare students, 3rd edition, Wolter Kluwer
Publications, Pg no:481-483.
2. Tortora G.J., Principles of Anatomy and Physiology, 12th edition,
Volume 2.
3. Ross and Wilson; Textbook of Anatomy and Physiology.
