Clinical Female Reproductive Anatomy

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Author: Dr Peter de Souza
Last modified: 28 December 2020


Ovaries and Fallopian Tubes


  • Ovarian Cyst Accidents
  • Polycystic Ovary Syndrome
  • Ovarian Cancer

Ovarian Cyst Accidents

Three things can happen with ovarian cysts:

  • Haemorrhage into the cyst
  • Rupture of the cyst into the peritoneal space
  • Ovarian torsion

Polycystic Ovary Syndrome

  • Endocrine disorder
  • Multiple enlarged follicles scattered underneath the surface of the ovary.


  • Polycystic ovaries on ultrasound
  • Irregular menstruation
  • Raised testosterone leading to hirsutism and acne

Ovarian Cancer

There are three main groups of cells within the ovary:

  • Epithelial Ovarian Cells: outer layer of cells, also known as the germinal epithelium
  • Germ cells: cells which make the eggs in the ovary
  • Connective tissue: supportive tissue of the ovaries
    • Granulosa cells
    • Thecal cells

Ovarian cancer can arise from any of these three main groups of cells, however the most common type comes from the surface epithelium.

This constitutes 80-90% of all ovarian cancers and is more common in older, post-menopausal women.

Serous type is most common type of surface epithelial ovarian cancer.

Germ cell cancers are more common in younger women.

Sex-cord stromal tumours are quite rare.


Fallopian Tubes

This fallopian tubes open DIRECTLY into the peritoneal cavity - this is the only direct communication with the intraperitoneal space.

This direct communication is a possible route for the spread of an infection - a sexually transmitted infection such as gonorrhoea, or chlamydia could spread into the peritoneum.

Ectopic pregnancy

Blastocyst implants in the wrong place, i.e. not in the endometrium.

Locations of ectopic pregnancy:

  • Fallopian tubes – this is the most common sites for ectopic pregnancy
    • Ampulla is the most common site in the fallopian tube for ectopic pregnancy
  • Cornua of the uterus
  • Cervix
  • Ovaries
  • Abdomen




Structures supporting the uterus:

  • Uterosacral ligament extending posteriorly from the cervix to the sacrum
  • Transverse cervical/cardinal ligament extending laterally to the pelvic side wall side wall
  • Pubocervical ligament extending anteriorly
  • Levator ani muscle

If these structures are weakened, then the pelvic organs can prolapse.

It is useful to think of the prolapses in terms of three different compartments:

Anterior Compartment

  • Urethrocele – urethra bulges into anterior wall of vagina.
  • Cystocele – bladder bulges  superiorly into anterior wall of vagina.
  • Urethrocele + cystocele = cystourethrocele.

Middle Compartment

  • Uterine prolapse
    • Graded from 1 to 3:
      • Grade 1: Prolapse contained within the vagina.
      • Grade 2: Further descent: cervix reaches level of introitus but the fundus stays inside the pelvis
      • Grade 3: the entire uterus is prolapsed outside the vagina – procidentia.
    • Causes of uterine prolapse are:
      • Previous vaginal delivery
      • Iatrogenic causes/previous pelvic surgeries
      • Low oestrogen levels in post-menopausal women
      • Obesity.
  • Enterocele – pouch of Douglas protrudes downwards.
  •  Vaginal vault prolapse -  Occurs after  a hysterectomy. The superior end of the vagina prolapses and the vagina inverts on itself.

Posterior Compartment

  • Rectocele

Benign Uterine Tumours

  • Fibroids
  • Intrauterine Polyps

Common causes for heavy menstrual bleeding (menorrhagia).


Uterine leiomyomata (leiomyoma = singular).

Benign tumours of smooth muscle and connective tissue differentiation, which affect the myometrium.

Three subtypes of fibroid:

  • Subserosal: just below the serous layer of the uterus
  • Intramural: directly within the wall of the myometrium.
  • Submucosal: underneath the mucosa.


Benign tumours which grow into the cavity of the uterus

Usually endometrial in origin

These cause menorrhagia and intermenstrual bleeding.


Characterised by ectopic endometrial tissue (areas of endometrial tissue that is out of place)

This tissue is responsive to oestrogen, just like the endometrium and therefore changes in size during the menstrual cycle as hormone levels change.

Chronic, cyclical pelvic pain is a common symptom of endometriosis.

Within the pelvic cavity, the common sites for endometriosis are

  • Ovaries
    • Chocolate cysts (endometrioma): accumulations of blood which appear a dark brown colour.
  • Pouch of Douglas (rectouterine pouch)
  • Vesicouterine pouch
  • Uterosacral ligaments
  • Fallopian tubes

Also affects: rectum, vagina, bladder

Sites outside of the pelvic cavity can also be affected:

  • Umbilicus
  • Old wound scars
  • Pleura
  • Pericardium
  • CNS

Long-term, endometriosis can lead to pelvic adhesions, and to immobile pelvic viscera.


Ectopic endometrial tissue within the myometrium

Endometrial cancer

Most common malignancy of the female reproductive tract

Mostly adenocarcinoma

Prolonged exposure to unopposed oestrogen (oestrogen without the protective effects of progesterone) is the biggest risk factor




  • portion of the vagina which protrudes into the vagina
  • squamous epithelium


  • lines the endocervical canal
  • columnar epithelium

Squamocolumnar junction occurs where the squamous epithelium meets the columnar epithelium

During puberty and pregnancy, the cervix gets pushed out and the columnar cells of the endocervix are exposed to the acidic environment of the vagina.

This causes metaplasia of the columnar cells to squamous cells and this area of change is called the transformation zone.

At the transformation zone, the cervix is more susceptible to neoplastic change.

Cervical ectropion

Benign condition of the cervix where the cervix protrudes out, exposing the columnar cells of the endocervix.

Results in a red area around the external os and is a common cause of post-coital bleeding (bleeding after intercourse).

Normal finding in:

  • younger women
  • pregnant women
  • women using the combined oral contraceptive pill

Cervical intra-epithelial neoplasia (CIN)

Pre-malignant, pre-invasive stage of cervical cancer.

Atypical cells can be detected by a smear test

Smear test is a cytological test, which detects cellular changes, not histological changes.

The degree of cellular change (dyskaryosis) corresponds to the degree of CIN

Three grades of CIN:

  • CIN 1: mild dysplasia  - affects lower 1/3 of epithelium.
  • CIN 2: moderate dysplasia – affects lower 2/3 of epithelium.
  • CIN 3: severe dysplasia – full thickness. Carcinoma in situ

Cervical cancer

Most often occurs near the external os, at the transformation zone.

Most common cause is human papillomavirus (HPV)

Squamous cell carcinoma (SCC) is the most common type

Adenocarcinoma is the second most common type.

Ovary and Fallopian Tubes

OK so in this tutorial I would like to introduce you to some clinical aspects in relation to the anatomy that I've discussed in the previous tutorials on the female reproductive anatomy.


We’ll start from the top and work our way down, so we'll begin with the ovaries, and look at some of the clinical aspects to consider in relation to the anatomy.


Ovarian Cyst Accidents

There are three things I'm going to talk about in relation to the ovaries, so the first is "ovarian cyst accidents".  The ovaries can develop cysts within them, and an ovarian cyst is a fluid-filled sac.


And the problem with these cysts is that the cysts can rupture, or they can cause the ovary to twist, which compromises its blood supply, and can lead to infarction and ultimately necrosis and death of the ovary.  Remember that the ovaries are suspended in the peritoneal cavity by the mesovarium.


I've just draw on an outline of a cyst on the ovary and you can get three things that happen. You can get haemorrhage into the cyst itself, you can get rupture of the cyst, so you'll get rupture into the peritoneal space, or the cyst can become so big that it actually causes the ovary to twist round on itself and you get a compromised supply of blood to the ovary.


Polycystic Ovary Syndrome

Another condition to do with ovaries is polycystic ovary syndrome, so in this condition, the ovaries are stimulated to produce excessive male hormone, so predominantly testosterone.


And in this condition you get multiple enlarged follicles which are actually scattered underneath the surface of the ovary, and they are themselves contained within an enlarged ovary.


The syndrome isn't just related to the ovaries, it's an endocrine disorder. And the criteria is obviously to have the polycystic ovaries themselves, which can be detected on ultrasound, and you also get irregular periods, and as a result of the raised testosterone, you get hirsutism, which is an excess of body hair, and you also get acne.  In terms of ovarian malignancy, there are three main groups to think about.


Ovarian Cancer

Thinking about the histology of the ovary, you've got epithelial ovarian cells, which is the outer layer of cells, and is called the germinal epithelium. And then you've got the germ cells themselves, which are the cells which make the eggs in the ovary. And then you've got the connective tissue - the supportive tissue of the ovaries, so you've got the granulosa and the thecal cells.


Ovarian cancer can arise from any of these three main groups of cells, but the most common, the type of cancer which makes up 80-90% of all ovarian cancers, comes from the surface epithelium, and this type of cancer is most common in older women, who are post-menopausal.

There are several different types of epithelial cancers, but the most common is the serous type. Germ cell cancers are more common generally in younger women, and sex-cord stromal tumours are quite rare.

Those are some clinical considerations in relation to the ovary.


Fallopian Tubes

Moving on to the fallopian tubes, remember how I said the ovum is released from the ovary, and it's wafted into the end of the fallopian tube by the finger-like projections.


What is happening is that the egg is actually released into the peritoneal space, and this is important, because the fallopian tubes open directly into the peritoneal cavity and this is the only direct communication with the intraperitoneal space.


Why is this important?


Well this is, this direct communication is a possible route for the spread of an ascending infection, so sexually transmitted infections like gonorrhoea, or chlamydia can potentially ascend and spread into the peritoneum.


Ectopic Pregnancy

The fallopian tubes are also one of the most common sites for ectopic pregnancies to occur.  An ectopic pregnancy is where the blastocyst implants in a site other than the endometrium of the uterine body.


So 95% of the time, the site will be in the fallopian tube, but the blastocyst can also implant ectopically in the cornu of the uterus, in the cervix, even in the abdomen.


The most common site within the fallopian tube itself for the ectopic pregnancies is in the ampulla.  Remember you've got the infundibulum, the ampulla, the isthmus and the intrauterine part.


The fate of an ectopic pregnancy located in the fallopian tube is that it may abort into the peritoneal cavity, or if it implants in the narrow isthmus section of the fallopian tube, it's much more likely to lead to a rupture of the tube.


A ruptured ectopic pregnancy and internal haemorrhage is a life-threatening condition and it needs to be treated immediately.  hopefully that has given you an idea of some of the clinical conditions associated with the ovaries and the fallopian tubes.

And next we'll take a look at the uterus and the associated clinical conditions.



So moving onto the uterus now, there are several things to talk about here; the first thing that I'm going to mention is prolapse.


If you remember some of the structures supporting the uterus, you've got the uterosacral ligament attaching from the cervix to the sacrum, the transverse cervical ligament attaching to the side wall, and the pubocervical extending anteriorly.


Together with the levator ani muscle, which you can see here, which forms the bulk of the floor of the pelvis, these structures support the uterus.  If these supporting structures are weakened, then you can descent of the pelvic organs.


The most important ones are the cardinal ligaments, and the uterosacral ligament, as well as the levator ani muscle, which supports all the pelvic viscera, and has a sort of sphincter function around them.



In terms of the types of the prolapse you can get, it's useful to think in terms of anterior, middle and posterior compartments.  Anteriorly, you can get a bulging out of the urethra into the anterior vaginal wall, like that, so this is called a urethrocele.


And likewise, you can get the bladder bulging into the anterior wall, a little bit higher up, so that's called a cystocele.  If you get both of the two bulging into the vaginal wall, this is called a cystourethrocele.  In terms of the middle compartment, you can obviously get the uterus itself prolapsing through the vagina.


And a uterine prolapse is graded from 1 to 3 depending on the extent of the descent of the uterus through the vagina.


A grade 1 prolapse is only slight descent, so you get prolapse that is contained within the vagina.


In a grade 2 prolapse, the descent is further, so you've got the cervix reaching the level of the introitus, but the fundus of the uterus remains inside the pelvis.


A grade 3 prolapse is when you've got the entire uterus, prolapsed outside the vagina, and this is also referred to as procidentia.


The causes of prolapse are childbirth - so a vaginal delivery, and then you've iatrogenic causes, so previous pelvic surgeries, and in post-menopausal women, with low oestrogen levels, you've got more lax ligaments and the uterus is more likely to prolapse.


And also if there's significant weight adding pressure to these structures, such as in obesity, that can predispose to uterine prolapse. And then also in the middle compartment, remember just behind the uterus and posterior to the supra-vaginal region, you've got the pouch of Douglas, which is this pouch of peritoneum.


So when this herniates down, this is known as an enterocele, and it bulges into the posterior wall behind the uterus.


Another type of prolapse in the middle compartment, is the vaginal vault prolapse, this is something you get after hysterectomy, where the superior end of the vagina prolapses, and you get inversion of the vagina.


And finally in the posterior compartment, as you may be able to guess, the rectum can protrude forwards, into the posterior wall of the vagina, and this is called a rectocele.  moving on, the next thing I'd like to talk about, are benign tumours of the uterus.


Benign Tumours

Two common benign tumours of the uterus are known as fibroids and intrauterine polyps.  These two combined - fibroids and polyps are very common causes for heavy menstrual bleeding, which is known as menorrhagia.


There are several causes for menorrhagia, but fibroids and polyps are two of the most common pathological causes for heavy bleeding.



Fibroids are known as uterine leiomyomata, so the singular for leiomyomata is leiomyoma.


These are benign tumours of smooth muscle and connective tissue differentiation. And they affect the myometrium of the uterus.  There are three subtypes of fibroid, depending on the location within the myometrium.


Remember the outer layer of the uterus is called the perimetrium.  this is the outer serosa layer of the uterus, so a fibroid located just below the serous layer is called a subserosal fibroid.


Fibroids located directly within the wall of the myometrium are called intramural.  The word mural just refers to the Latin "murus", which wall. And the final type of fibroid is one which lies just underneath the endometrium, underneath the mucosa, so this is called a submucosal fibroid.


Like I mentioned, fibroids are a common cause for menorrhagia, but they also cause pain, which is called dysmenorrhoea, and then you can have other effects from the fibroids, due to local pressure effects, so a large fibroid could put pressure on the bladder, leading to frequency or urinary retention.



Polyps are benign tumours which grow into the cavity of the uterus, intrauterine polyps are generally endometrial in origin, and they just grow out into the cavity itself of the endo, of the uterus sorry. So similarly, these cause menorrhagia and they can also be responsible for intermenstrual bleeding.



Another common condition, which doesn't really directly relate to the uterus itself, but I'm mentioning it here because it's a condition which is characterised by ectopic endometrial tissue.


You get areas of endometrial tissue that is out of place, and this condition is known as endometriosis.  within the pelvic cavity itself, the common sites for endometriosis are the ovaries, which you can see here. And in this model, it's actually been dissected away, and you can see this brown coloured stuff.


These are called chocolate cysts. And these are essentially accumulations of blood which appear this dark brown colour.  these chocolate cysts are also known as endometrioma. And then as you can see here, endometriosis has an affinity for the pouch of Douglas, so the recto-uterine pouch.


It can also be found in the vesico-uterine pouch as well. And other common sites are the utero-sacral ligaments, and it also affects the uterine tubes.  Endometriosis isn't actually confined only to the, to the pelvic cavity, it also affects the umbilicus, it can affect wound scars, it can affect the pleura, the pericardium and even the central nervous system.


Other sites in the pelvic cavity involve the rectum, the vagina and the bladder.  This ectopic endometrial tissue is just like the endometrial tissue itself.


It’s responsive to changes in hormones, so it actually increases and decreases in size according to the hormonal stage of the menstrual cycle, so its oestrogen sensitive tissue, and it therefore regresses after the menopause when oestrogen levels drop, and also during pregnancy.


Long term, endometriosis can actually cause adhesions between the pelvic viscera, and you can get fibrosis ultimately of the pelvic organs.  The symptoms you get are, sort of chronic pelvic pain that's cyclical in nature.



You can also get ectopic endometrial tissue within the myometrium. And this is known as adenomyosis.  In this condition, symptoms may be absent, but you often get menorrhagia and painful periods, so dysmenorrhoea.


Endometrial Cancer

Finally just to mention a malignant condition, so endometrial cancer, which is cancer of the endometrium, is the most common malignancy of the female reproductive tract.


It's mostly adenocarcinoma, and it is an oestrogen dependent tumour, so risk factors for endometrial cancer relate to prolonged exposure to unopposed oestrogen, and that's the main risk factor.


Unopposed just means there is no progesterone along with the oestrogen to modulate the effects of oestrogen - it doesn't have that protective effect of the progesterone.


Hopefully that should have given you an idea of some of the main clinical conditions associated with the uterus.



Next I'd like to move onto the cervix, so what we're looking at here, is the cervix bulging into the end of the vagina.



The portion of the cervix projecting into the vagina is known as the ectocervix, and I've outlined this in blue. And then you've got the bit which lines the canal, which lies inside the cervix.


This is the endocervical canal.  You’ve got the ectocervix and the endocervix.  the endocervix is lined with columnar epithelium, whereas the ectocervix, which is continuous with the vagina, is lined with squamous epithelium.


Where the columnar epithelium meets the squamous epithelium, is called the squamocolumnar junction.  During pregnancy and during puberty, you get eversion of the cervix, you get the pushing out of these columnar cells, which line the endocervix and as a result they're then exposed to the acidic environment of the vagina.


What happens when the columnar epithelium are exposed to this acidic  environment, is that you get metaplasia, which is a changing of the cell type from columnar to squamous epithelium.



And this area of change from columnar to squamous is called the transformation zone, and this zone is important because at this area, the cervix is susceptible to neoplastic change and ultimately, to possibility of cervical carcinoma, so a common benign condition to be aware of is a cervical ectropion, which is also called a cervical erosion, so like I just mentioned, during puberty and during pregnancy, the cervix protrudes out and you get exposure of the columnar cells to the vagina.


On speculum examination, you can see the ectropion, or erosion, around the cervical os, and it's visible as a sort of reddish area, so this is a normal finding in younger women, pregnant women, and those women who are use the pill. And it often presents with post-coital bleeding, so that's bleeding after intercourse.


Cervical intraepithelial neoplasia

Two other important conditions to talk about are the premalignant, preinvasive stage of cervical cancer, which is called "cervical intraepithelial neoplasia", and the other is malignant carcinoma of the cervix.  On the left here I've drawn a very quick diagram of a layer of epithelial cells, sitting upon the basement membrane.  Invasive cancer is cancer that has spread through the basement membrane.


Cervical intraepithelial neoplasia, or CIN, is this preinvasive stage of cervical cancer, so it hasn't yet gone through the basement membrane.


So in this premalignant condition, you've got atypical cells, you've got dysplastic cells and the way that it's detected is often with a smear test.


A smear test is a cytological test, where cells are sampled from this transformation zone of the cervix, which is the most common origin, or location for cells to undergo this dysplastic change.


It’s important to note that the smear is a cytological test, it detects cellular changes rather than histological changes, but the degree of dyskaryosis, which is the degree of cellular change, actually reflects the severity of the CIN, the cervical intraepithelial neoplasia. And these cellular changes are changes in the nuclear size and also changes in the rate of mitotic division.


Essentially, it's a histological diagnosis, but the cellular changes do correspond to what is actually seen on histology.


There are three grades of CIN, so in grade 1, you've got mild dysplasia, and this affects the lower third of the epithelium.


In CIN 2, you've got moderate dysplasia, which affects the lower two thirds, of the epithelium, and in CIN 3, you've got full thickness involvement of the epithelium. This is called carcinoma in situ. At this stage, if the abnormal cells invade through the basement membrane, you have cervical cancer.


In cervical carcinoma, it most often occurs near the external os, at the transformation zone, and one of the most common causes is the human papillomavirus - HPV, and 90 percent of the time, cervical carcinoma is of the squamous type, so it's squamous cell carcinoma, or SCC.


And the second most common type is adenocarcinoma, which involves cells of glandular origin. So those are some important conditions to be aware of in relation to the cervix.