The Female Internal Genital Organs
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bladder and urethrae | Main Anatomy Index | The ovaries
Last updated 30 March 2006
The Female Internal Genital Organs
- The genitalia or genital organs consist of internal and external structures.
- The female internal genital organs include the vagina, uterus, uterine tubes and ovaries.
- This is the female organ of copulation and is a fibromuscular tube
or sheath lined with stratified squamous epithelium.
- It forms the inferior portion of the female genital tract
and the birth canal.
- The vagina communicates superiorly with the cervical canal
and opens inferiorly into the vestibule of the vagina.
- In the anatomical position, the vagina descends anteroinferiorly.
- Its anterior and posterior
walls are normally in apposition, except at its superior end where the cervix of
the uterus enters its cavity.
- The posterior wall is about 1 cm
longer than the anterior wall and is in
contact with the external uterine ostium (external os).
- The cervix of the uterus projects into the superior part of the anterior wall,
separating the walls of the vagina.
- The uterus lies almost at a right angle
to the axis of the vagina (anteverted position). This uterine angle increases as the urinary bladder fills.
- The vaginal recess around the cervix is called the fornix (L. arch).
- It is divided into anterior, posterior,
and lateral parts.
- The posterior part of the fornix
is the deepest and is related to the rectouterine
The Relations of the Vagina
- The superior limit of the vagina is the 1 to 2 cm of its posterior wall
covering the posterior part of the fornix.
- This part is usually covered by peritoneum.
- A penetrating wound to this part of the vagina may
involve the peritoneal cavity.
- Inferior to the posterior part of
the fornix, there is only the loose connective tissue of the rectovaginal
septum separating the posterior wall from the rectum.
- This then can be palpated in the rectum.
The Sphincters of the
- There are 3 muscles that can compress the vagina and
act like sphincters:
- The pubovaginalis muscle, the anterior part of the levator ani;
- The urogenital
- And the bulbospongiosus muscle.
The Arterial Supply of
- The vaginal artery is usually a branch
of the uterine
- It may, however, arise from the internal iliac artery.
- The 2 vaginal arteries anastomose with each other and
with the cervical branch of the uterine artery.
- The internal pudendal artery and vaginal
branches of the middle rectal artery also
supply the vagina (branches of the internal iliac arteries).
- These arteries form anterior and posterior
azygos arteries to supply the vaginal wall.
The Venous Drainage of
- The vaginal veins form vaginal venous plexuses along
the sides of the vagina and within its mucosa.
- Drainage is into the internal iliac veins.
- They communicate with the vesical, uterine,
and rectal venous plexuses.
Drainage of the Vagina
- The lymph vessels from the vagina are in 3 groups:
- Those from the superior part accompany the uterine artery and drain into the internal
and external iliac lymph nodes;
- Those from the middle part accompany the vaginal artery and drain into the internal
iliac lymph nodes;
- And those from the vestibule drain into the superficial inguinal lymph nodes.
- Some lymph from the vestibule drain into the sacral and common iliac lymph nodes.
Innervation of the Vagina
- The vaginal nerves are derived from the uterovaginal plexus.
- This lies in the base of the broad
ligament on each side of the supravaginal part of the
- The inferior nerve fibres from this plexus supply the cervix and the superior part
of the vagina.
- The fibres supplying the vagina are derived from the inferior hypogastric plexus and the pelvic
- The inferior part of the vagina is supplied by the pudendal nerve.
Click here for a schematic diagram of the uterus.
- This is a hollow, thick-walled,
pear-shaped muscular organ located between the bladder and the rectum (in non-pregnant women).
- It is 7 to 8 cm long, 5 to 7 cm
wide, and 2 to 3 cm thick.
- The uterus normally projects superoanteriorly over the urinary bladder.
- During pregnancy, the uterus enlarges
greatly to accommodate the embryo and later the foetus.
- The uterus consists of 2 major parts:
- The expanded superior 2/3 is known as the body;
- The cylindrical inferior 1/3 is called the cervix (L. neck).
- The uterus is usually bent anteriorly (anteflexed) between the cervix
- The entire uterus is normally bent or inclined anteriorly
- It is frequently retroverted (inclined posteriorly) in older women.
The Fundus of the Uterus
- The fundus of the uterus is the rounded
superior part of the body.
- It is located superior to the line joining the points
of entrance of the uterine tubes.
- The regions of the body where the uterine tubes enter
are called the cornua (L. horns).
The Cervix of the Uterus
- As the cervix projects into the vagina, it is divided
into vaginal and supravaginal parts.
- The rounded vaginal part communicates with the vagina
via the external ostium of the uterus (L. ostium,
door, entrance or mouth).
- The ostium is bounded by anterior and posterior lips formed by the cervix.
The Isthmus of the Uterus
- This is about 1 cm long and is the narrow
transitional zone between the body and cervix.
- This slight constriction is most obvious in nulliparous women.
The Wall of the Uterus
- The wall of the uterus consists of 3 layers:
- The outer serous coat called the perimetrium,
consists of peritoneum supported by a thin layer of
- The middle muscular coat called the myometrium
consists of 12 to 15 mm of smooth
muscle. The myometrium increases greatly
during pregnancy. The main branches of the blood vessels and nerves of
the uterus are located in this layer;
- The inner mucous coat called endometrium
is firmly adherent to the underlying myometrium.
- The endometrium is partly sloughed off each month
- It lines only the body of the
Borders of the Uterus
- The uterus has an anteroinferior or vesical
surface related to the urinary bladder.
- There is also a posterosuperior or intestinal
surface related to the intestine.
- These convex surfaces are separated
by right and left borders.
- Each uterine tube enters the lateral
border of the body of the uterus near its superior end.
- The tube opens at one end into the peritoneal cavity
near the ovary and at the other end into the uterine
- The ligaments of the ovaries are attached to the
uterus, posteroinferior to the uterotubal
- The round ligaments of the uterus are attached anteroinferiorly to these junctions.
The Ligaments of the Uterus
Click here for schematic diagrams of the ligaments
of the uterus.
Ligament (Cardinal Ligament)
The Uterosacral Ligaments
- These pass superiorly and slightly
posteriorly from the sides of the cervix to
the middle of the sacrum.
- They are deep to the peritoneum
and superior to the levator ani muscles.
- The uterosacral ligaments tend to hold the cervix in
its normal relationship to the sacrum.
The Round Ligament of the
- These ligaments are 10 to 12 cm long and extend for the
lateral aspect of the uterus,
passing anteriorly between the layers of the broad ligament.
- They leave the abdominal cavity through the inguinal canal and insert into the labia majora.
The Broad Ligament
- This is a fold of peritoneum with mesothelium
on its anterior and posterior
- It extends from the sides of the uterus to the lateral walls and floor of the pelvis.
- The broad ligament holds the uterus in its normal position.
- The 2 layers of the broad ligament are continuous with each other at a free edge.
- This is directed anteriorly and superiorly
to surround the uterine tube.
- Laterally, the broad ligament is prolonged
superiorly over the ovarian vessels as the suspensory ligament of the ovary.
- The ovarian ligament lies posterosuperiorly
and the round ligament of the uterus lies anteroinferiorly within the broad ligament.
- The broad ligament contains extraperitoneal tissue
(connective tissue and smooth muscle) called parametrium.
- It gives attachment to the ovary
through the mesovarium.
Support of the Uterus
- This is the pelvic floor, formed by the pelvic diaphragm.
- The pelvic viscera surrounding the uterus and the visceral fascia (endopelvic fascia) bind
the pelvic viscera together.
The Relationships of the
- Anteriorly the body of
the uterus is separated from the urinary bladder by the vesicouterine pouch.
- Here, the peritoneum is reflected
from the uterus onto the posterior margin of
the superior surface of the bladder.
- The vesicouterine pouch is empty when the uterus is in its normal position.
- Posteriorly the body
of the uterus and the supravaginal part of the cervix are
separated from the sigmoid colon by a
layer of peritoneum and the peritoneal
- The uterus is separated from the rectum by the rectouterine pouch (of Douglas).
- The inferior part of this pouch
is closely related to the posterior part of the fornix of the vagina.
- Laterally the relationship of the ureter to the uterine
artery is very important.
- The ureter is crossed superiorly
by the uterine artery at the side
of the cervix.
Arterial Supply of the
- This is derived mainly from the uterine arteries, which
are branches of the internal iliac arteries.
- They enter the broad
ligaments beside the lateral parts of the fornix of the vagina, superior to the ureters.
- At the isthmus of the uterus, the uterine
artery divides into a large ascending branch
that supplies the body of the uterus and a small descending branch that supplies the
cervix and vagina.
- The uterus is also supplied by the ovarian arteries,
which are branches of the aorta.
- The uterine arteries pass along the sides
of the uterus within the broad ligament and then turn laterally at the entrance to the
uterine tubes, where they anastomose with the ovarian
Venous Drainage of the
- They form a uterine venous plexus on each side of the cervix and its tributaries drain into the internal
- The uterine venous plexus is connected with the superior rectal
vein, forming a portal-systemic anastomosis.
of the Uterus
- The lymph vessels of the uterus follow three main routes:
- Most lymph vessels from the fundus pass with the ovarian vessels to the aortic lymph nodes,
but some lymph vessels pass to the external iliac lymph nodes
or run along the round ligament of the uterus to
the superficial inguinal lymph nodes.
- Lymph vessels from the body pass through the broad ligament to the external iliac
- Lymph vessels from the cervix pass to the internal iliac and sacral lymph nodes.
Innervation of the Uterus
- The nerves of the uterus arise from the inferior hypogastric
plexus, largely from the anterior and intermediate part known as the uterovaginal
- This lies in the broad ligament on each side of the cervix.
- Parasympathetic fibres are from the pelvic
splanchnic nerves (S2-4), and sympathetic fibres are from the above plexus.
- The nerves to the cervix form a plexus
in which are located small paracervical ganglia.
- One of these are large and is called the uterine cervical ganglion.
- The autonomic fibres of the uterovaginal
plexus are mainly vasomotor.
- Most the afferent fibres ascend through the inferior hypogastric plexus and enter the spinal cord via T10-12 and L1 spinal nerves.
The Uterine Tubes
- These are 10 em long and 1 cm in
- They extend laterally from the cornua
of the uterus.
- The uterine tubes carry oocytes from the ovaries and sperm cells from
the uterus to the fertilisation site
in the ampulla of the uterine tube.
- The uterine tube also conveys the dividing zygote to
the uterine cavity.
- Each tube opens at its proximal end into the cornua or horn of the uterus.
- At its distal end, it opens into the peritoneal
cavity near the ovary.
- The uterine tubes allow communication between the peritoneal
cavity and the exterior of the body.
of the Uterine Tube
- This is the funnel-shaped lateral
or distal end of the uterine tube.
- It is closely related to the ovary.
- Its opening into the peritoneal cavity is called the abdominal ostium.
- About 2 mm in diameter, the ostium
lies at the bottom of the infundibulum.
- Its margins have 20 to 30 fimbriae (L. fringes).
- These finger-like processes spread over the surface of the ovary, and a large one, the ovarian fimbria,
is attached to the ovary.
- During ovulation the fimbriae trap the oocyte and sweep it through the abdominal ostium
into the ampulla.
The Ampulla of the
- This begins at the medial end of the infundibulum.
- It is in this tortuous part that fertilisation
of the oocyte by a sperm usually occurs.
- The ampulla is the widest and longest
part of the uterine tube, making up over half of its
The Isthmus of the
- This is the short (about 2.5 cm),
narrow, thick-walled part
of the uterine tube.
- It enters the cornu of the uterus.
(Uterine) Part of the Uterine Tube
- This part of the tube is the short segment that passes through the thick myometrium of the uterus
and opens via the uterine ostium into the uterine cavity.
- This opening is smaller than the abdominal
- The uterine tubes lie in the free edges of the broad ligaments of the uterus.
- The part of the broad ligament attached to the uterine tube is called the mesentery of the tube or mesosalpinx
(G. salpinx, a tube).
of the Uterine Tubes
- The arteries to the tubes are derived from the uterine
and ovarian arteries.
- The tubal branches pass to the tube between the layers
of the mesosalpinx.
of the Uterine Tubes
- The veins of the tubes are arranged similarly to the arteries
and drain into the uterine
and ovarian veins.
Drainage of the Uterine Tubes
- The lymph vessels of the uterine tubes follow those of
the fundus of the uterus and ovary
and ascend with ovarian veins
to the aortic lymph nodes in the lumbar
Innervation of the
- The nerve supply of the uterine tubes comes partly from the ovarian
plexus of nerves and partly from the uterine plexus.
- Afferent fibres from the tubes are contained in T11-12 and L1 nerves.