Session 2 Flashcards
Describe the internal and external genitalia of the female LO/ Describe and identify the main anatomical structures of the female reproductive tract LO
- State the internal & external genitalia of the female
- Internal:
- ovaries
- Fallopian tubes
- uterus
- cervix
- vagina?
External:
- labia majora (labioscrotal swellings)
- labia minora (urethral folds)
- vestibule
- bartholian glands (secrete mucus)
- clitorus (genital tubercle) + prepuce
- mons pubis
- Vaginal herpes is most commonly caused by?
- Symptoms include:
- What is located laterally to the vagina?
- Herpes simplex Type II virus
- localised itching and burning
- painful red vesicles ~3 days after infection
- may ulcerate and last up to 2 weeks, sometimes with recurrent attacks
- localised itching and burning
- Ureters & uterine arteries
Next to the lateral fornix (es)
What is a vaginal fistula? Cause? There are three main types of vaginal fistula what are they?
Connection between vagina & adjacent pelvic organ
prolonged labour (fetus exerts pressure on vaginal wall, limits blood supply resulting in necrosis)
Vesicovaginal - urine constantly enters the vagina
Urethrovaginal - urine enters vagina only when urination occurs
Rectovaginal - feaces can enter the vagina
The vagina is composed of 4 histological layers (internal to external)
Stratified squamous epithelium – protection
Lubricated by cervical mucus (the vagina itself does not contain any glands).
Oestrogen stimulates the epithelial cells to secrete glycogen. The glycogen is digested by lactobacilli to produce lactic acid, and maintain a low vaginal pH of ~4.5 (prevents infection)
Elastic lamina propria – a dense CT layer which projects papillae into the overlying epithelium. Larger veins are located here (Lamina propria & epithelium = vaginal mucosa )
Fibromuscular layer – two SM layers; an inner circular & an outer longitudinal layer
Adventitia – a fibrous layer, provides strength to the vagina & binds it to surrounding structures
- Describe the arterial supply and venous drainage of the uterus
- Internal iliac artery -> uterine & vaginal arteries
vaginal venous plexus -> uterine vein -> internal iliac veins
iliac and superficial inguinal lymph nodes
- What epithelium is present in the cervix?
- Ectocervix: stratified squamous non-keratinized epithelium
Endocervix: mucus-secreting simple columnar epithelium
Ectocervical canal (external os) vagina
endocervical canal (internal os) uterine cavity
- How do we describe the uterus?
- The uterus may not lie in an anterverted & anteflexed position, how else may it lie?
- Anteverted: (vagina & cervix )
Anteflexed: (cervix & uterus)
- Excessively anteflexed
Anteflexed and retroverted
Retroflexed and retroverted
Relate female reproductive tract anatomy to common clinical problems LO
Which position of the uterus can cause problems and why
Retroverted- uterus directly above the vagina – increased abdominal pressure uterus prolapse in the vagina (common in those with pelvic floor damage)
The fundus and body of the uterus are composed of three tissue layers;
Peritoneum: A double layered membrane (also known as the perimetrium)
Myometrium: smooth muscle layer. Cells of this layer undergo hypertrophy and
hyperplasia during pregnancy in preparation to expel the fetus at birth.
Endometrium: An inner mucous membrane lining the uterus. It can be further subdivided into 2 parts – the stratum basalis and the stratum functionalis:
Anterior to the uterus is the ? of peritoneum separating it from the bladder
Posterior to the uterus is the ? separating it from the rectum
uterovesical pouch, rectouterine/pouch of Douglas
How might the pouch of Douglas be reached?
What two ligaments support the uterus?
- posterior fornix
- culdocentesis
Transverse cervical ligament – attaches laterally
Uterosacral ligament – attaches posteriorly
- Why might we perform a hysterectomy?
- What must we remember in this procedure?
- What is endometriosis?
- Why is this dangerous?
- What are fibroids?
- They are oestrogen dependent, enlarging during pregnancy and with use of the contraceptive pill but regressing after the menopause. Most fibroids are asymptomatic, but if large enough the uterine mass can cause symptoms including ?
- Removal of the uterus i.e. cancer
- when we clamp the uterine arteries be careful of the ureters
- ectopic endometrial tissue at sites outside the uterus, most commonly the ovaries & the ligaments of the uterus
- responsive to oestrogen = cyclic proliferation and bleeding occur, often forming a cyst
The condition is associated with dysmenorrhoea and/or infertility.
- Benign tumours of the endometrium
- menorrhagia, pelvic pain & infertility
- Describe the layers/ epithelium present in the Fallopian tubes
- What is the structure of the uterine tubes?
- The inner mucosa is lined with ciliated columnar epithelial cells and peg cells (non-ciliated secretory cells). They waft the ovum towards the uterus and supply it with nutrients.
Smooth muscle layer contracts to assist with transportation, SM is sensitive to sex steroids, and thus peristalsis is greatest when oestrogen levels are high.
2.
State the arterial and venous blood supply to the uterine tubes.
- Uterine & ovarian arteries
- Venous drainage is via the uterine and ovarian veins.
Lymphatic drainage is via the iliac, sacral and aortic lymph nodes.
- What is salpingitis
- In both the males and females, the gonads develop within the ? and descend through the abdomen. However, unlike the testes, the ovaries stop in the pelvis.
- Inflammation of the Fallopian tube
usually due to infection
adhesions within tube
sperm can pass through = ectopic pregnancy
haemorrhage
- mesonephric ridge
- Ovaries descend like the testes but stop in the pelvis as they are physically halted by ?
- What are ovarian cysts
- Complications of ovarian cysts
- Developing uterus from the paramesonephric ducts
- Fluid filled masses that may develop in the ovary. They are most commonly derived from ovarian follicles.
- bleeding
- pain = surgical removal
- bleeding
- What is polycystic ovaries characterised by?
- Two peritoneal ligaments attach to the ovary;
- The broad ligament is a flat sheet of ?, associated with the uterus, fallopian tubes and ovaries. It extends from the ? on both sides, and folds over the internal female genitalia, covering their surface ?
- Hormone dysfunction, over 10 ovarian cysts & associated with infertility.
- Suspensory ligament of ovary: fold of peritoneum extending from the mesovarium to the pelvic wall. Contains neurovascular structures.
Ligament of ovary: extends from the ovary to the fundus of the uterus. It then continues from the uterus to the connective tissue of the labium majus, as the round ligament of uterus.
- peritoneum, lateral pelvic walls, anteriorly and posteriorly
- What is the key to sexual dymorphism?
- Label the diagram
- Where do primordial germ cells originate from? What is the journey of the primordial germ cells?
- Testis-determining gene: SRY(sex-determining region on Y) gene on its short arm (Yp11)
- Epiblast
migrate through the primitive streak,
yolk sac close to the allantois
dorsal mesentery of the hindgut into the retroperitoneum
Arriving at the primitive gonads
Invading the genital ridges
- Function of the primordial germ cells?
- What happens before the primordial cell arrive?
- What forms due to the SRY gene?
- What happens to the sex cords once the testes determining factor is formed?
- Inductive influence of gonad into ovaries or testes
- primitive sex cords form (gonad is known as the indifferent gonad- in both male & females)
- Testes determining factor:
– gonad (testis)
– Production of testicular hormones
– internal genitalia (male duct system)
- primitive sex cords continue to proliferate
- cords break at hilum give rise to the rete testis
- tunica albuginea (fibrous tissue which separates the testis cords from the surface epithelium)
- primitive sex cords continue to proliferate
- What happens to the sex cords in a male?
- What happens to the sex cords in a female?
- solid sex cords
At puberty acquire a lumen = seminiferous tubules
Once canalized they join the rete testis tubules, which enter the ductuli efferents, which enter the vas deferens
- Form cell clusters (contain primitive germ cells) which are replaced by stroma that forms the ovarian medulla
surface epithelium of the female gonad continues to proliferate -> 7th week it second generation of cords, cortical cords -> 3rd month cords split into isolated cell clusters -> proliferate and begin to surround each oogonium with a layer of epithelial cells called follicular cells. Together, the oogonia and follicular cells constitute a primordial follicle
What is the relationship of the paramesoneprhic duct to:
- Abdominal cavity
- Mesonephric duct
- Paramesonephric duct on the contralateral side
- Cranially, the duct opens into the abdominal cavity
- Caudally, it first runs lateral to the mesonephric duct, then crosses it ventrally to grow
caudomedially - In the midline, it comes in close contact with the paramesonephric duct from the opposite side
- later fuses to form the uterine canal
- caudal tip of the combined ducts projects into the posterior wall of the urogenital sinus, where it causes a small swelling, the paramesonephric tubercle
What two hormones does the testis produce?
What cells produce these hormones?
What effect do they exert?
What ducts develop in females? Why?
No testis = no Sertoli cells = no Mullerian inhibiting hormone = No suppression of Mullerian (paramesonephric) duct development
No testis = no leydig cells = no testosterone = Wolffian (mesonephric) duct degenerates
After the ducts fuse in the midline, a broad transverse pelvic fold is established. This fold, which extends from the lateral sides of the fused paramesonephric ducts toward the wall of the pelvis, is the?
broad ligament of the uterus
- The wing-like expansions of the vagina around the end of the uterus, the vaginal fornices, are of ? origin
- The vagina has a dual origin, with the upper portion derived from the ? and the lower portion derived from the ?
- Paramesonephric origin
- uterine canal, urogenital sinus
Mesonephric duct functions in both male and female embryos as ?
? ducts appear in both
Mesonephric duct ceases to be of use to the urinary system and will degenerate unless ?
Paramesonephric duct regresses in the presence of ?
duct of embryonic kidney
Paramesonephric (Mullerian)
testis-derived testosterone is present
testis-derived MIH
- What is the most common cause of sexual ambiguity?
Congenital adrenal hyperplasia (CAH):
a. 21-hydroxylation is inhibited
decreased cortisol and an increase in adrenocorticotropic hormone (ACTH) increased testosterone
Females partial masculinization with a large clitoris to virilization and a male appearance.
b. 17α-hydroxylase deficiency (rarer)
females having female internal and external anatomy at birth
But failure of secondary sex characteristics to appear at puberty due to an inability of the adrenals or ovaries to produce sex hormones. Consequently, there is no breast development or growth of pubic hair. In males with 17α-hydroxylase deficiency, virilization is inhibited.
Androgen insensitivity syndrome (AIS)
Effects male
Lack of androgen receptors or failure of tissues to respond to receptor-dihydrotestosterone complexes.
No wolffian ducts
MIS(sertoli) is present = no paramesonephric ducts
CAIS: a vagina is present (short/ poorly developed)
The testes are frequently found in the inguinal or labial regions, but spermatogenesis does not occur.
Increased risk of testicular tumors
MAIS/ PAIS: virilization to varying degrees, but with the partial form ambiguous genitalia may be present, including clitoromegaly or a small penis with hypospadius. Testes are usually undescended in these cases.
Describe how the testes descend
- urogenital mesentery attaches the testis and mesonephros to the posterior abdominal wall
- degeneration of the mesonephros, the attachment serves as a mesentery for the gonad
- Caudally, it becomes ligamentous and is known as the caudal genital ligament
- Also extending from the caudal pole of the testis is a mesenchymal condensation rich in
extracellular matrices, the gubernaculum
- Later, as the testis begins to descend toward the internal inguinal ring, an extra-abdominal portion of the gubernaculum forms and grows from the inguinal region toward the scrotal swellings. When the testis passes through the inguinal canal, this extra-abdominal portion contacts the scrotal floor
