Female reproductive tract Flashcards
Name the 3 components of both the ‘upper’ and ‘lower’ female genital tracts
What divides them?
Upper (1/3rd) - Uterus, oviducts/fallopian tubes, ovaries.
Lower (2/3rd) - Cervix and vagina.
Endocervix – divides upper and lower.
What is the function of the uterus?
Secondary sex organ, capable of expansion to accommodate a growing foetus.
What are the two main subdivisions of the uterus?
The two main subdivisions of the uterus are the body and the cervix.
Body: Usual site for implantation of the blastocyst.
Cervix: Lower part of uterus linking it with the vagina. This part is structurally and functionally different to the rest of the uterus.
Another part of the uterus is the fundus - this is the top of the uterus, above the entry point of the uterine tubes.
What is meant by the internalos and externalos?
The opening into the uterus is called the internal os (orifice). It marks the narrowing at which the endocervical canal ends and the uterine cavity begins.
The opening into the vagina is called the external os (orifice). The ectocervix is the portions of the cervix that projects into the vagina. It marks the transitions from the ectocervix to the endocervical canal.
What is meant by the ‘version’ and ‘flexion’ of the uterus?
Version/Anteverted – The angle between the longitudinal axis of the cervix, and that of the vagina. Angle of cervix to vagina. This is when the uterus is rotated/displaced either forward (anteflexed) or backwards (retroverted).
Flexion/Anteflexed – The angle between the longitudinal axis of the uterus, and that of the cervix. Angle of uterus to cervix. This is when the uterus bends/folds onto itself either forwards (anteflexed) or backwards (retroflexed).
What are the main relations of the uterus?
Anteriorly related to the bladder.
Posteriorly related to the rectum.
What is the broad ‘ligament’?
What is the round ligament?
This is a double layer of peritoneum attaching the sides of the uterus to the pelvis. It acts as a mesentery for the uterus and contributes to maintaining it in position.
Round Ligament: A remnant of the gubernaculum extending from the uterine horns to the labia majora via the inguinal canal. It functions to maintain the anteverted position of the uterus.
What is the ‘ovarian/proper/utero-ovarian ligament’?
What is the Cardinal Ligament?
What is the Uterosacral Ligament?
Joins the ovaries to the lateral surface of the uterus.
Cardinal Ligament: Located at the base (inferior border) of the broad ligament, the cardinal ligament extends from the cervix to the lateral pelvic walls. It contains the uterine artery and vein in addition to providing support to the uterus. When a hysterectomy is being performed due to a malignancy, the cardinal ligaments are often removed as they are common reservoir of cancerous cells.
Uterosacral Ligament: Extends from the cervix to the sacrum. It provides support to the uterus.
What is the ‘suspensory/IP/infundibulopelvic ligament’ of the ovary’?
A fold of peritoneum that extends out from the ovary to the wall of the pelvis.
Why will the ovaries be very small in the cadaver?
Ovaries are small in post-menopausal women, ovarian volume DE with age.
What is the broad ligament divided into?
The broad ligament may be divided into three subcomponents:
Mesometrium
The mesentery of the uterus; the largest portion of the broad ligament.
Surrounds the uterus and is the largest subsection of the broad ligament. It runs laterally to cover the external iliac vessels, forming a distinct fold over them. The mesometrium also encloses the proximal part of the round ligament of the uterus.
Mesosalpinx
The mesentery of the Fallopian tube.
Originates superiorly to the mesovarium, enclosing the fallopian tubes.
Mesovarium
The mesentery of the ovaries.
Part of the broad ligament associated with the ovaries. It projects from the posterior surface of the broad ligament and attaches to the hilum of the ovary, enclosing its neurovascular supply. It does not, however, cover the surface of the ovary itself.
What is the blood supply of the uterus? From which artery does this arise?
Surgically, which important structure is related to this artery?
The uterus is supplied by the uterine artery which arises from the anterior division of the internal iliac artery. It crosses above the ureter on its course to the uterus (bridge over water). The uterine artery commonly anastomoses with the vaginal and ovarian arteries.
The uterine artery crosses the ureters approximately 1 cm laterally to the internal os. Care must be taken not to damage the ureters during clamping of the uterine arteries during a hysterectomy. The relationship between the two can be remembered using the phrase ‘water under the bridge’. Water refers to the ureter (urine), and the uterine artery is the bridge.
Name the 4 parts of the ‘uterine/fallopian tube’ (oviduct).
Isthmus – Narrow section of the uterine tubes connecting the ampulla to the uterine cavity
Ampulla – Widest section of the uterine tubes. Fertilization usually occurs here.
Infundibulum – Funnel-shaped opening near the ovary to which fimbriae are attached.
Fimbriae – Finger-like, ciliated projections which capture the ovum from the surface of the ovary. It engulfs the ovary, at ovulation, to receive the oocyte.
Where does fertilisation occur?
Fertilisation occurs in the ampullary segment of the fallopian tube. Transit time of the zygote from the ampulla to the ampulla-isthmic junction is approximately 30 hours, after which the zygote remains in the isthmus another 30 hours before resuming transit through the isthmus.
Which life threatening condition is associated with the uterine tube?
Ectopic pregnancy, occurs when the embryo does not implant in the uterus. In many cases, the embryo implants in a Fallopian tube. If not diagnosed early, the implanted blastocyst can cause rupture and haemorrhage of the affected tube.
Note that, developmentally, the ovaries (like the testes) arise, retro-peritoneally, on the posterior abdominal wall and then descend (but only to pelvic brim).