Uterus Flashcards
Describe the uterus
It is a pear shaped , thick hollow muscular organ.
It is 3 Inches long, 2 inches wide and 1inch thick.
The uterus is formed from 3 parts
Fundus
Body
Cervix
Describe the fundus
It is 2 inch long
It is the dome shaped upper part above the entrance of uterine tubes.
It is convex in all directions
Describe the body
It is 2 inch long
This passes downward from the fundus and is flattened anteroposteriorly.
Enclosed by the peritoneum that laterally becomes the broad ligament, it narrows to form the isthmus.
Describe the cervix
It is 1 inch long
The isthmus continues into the cervix, which is embraced by the vagina in its middle third.
It thus has vaginal and supravaginal parts.
Fornix of vagina surrounds the protruding cervix.
Its intestinal surface is covered by peritoneum forming rectouterine pouch and the vesical surface
has no peritoneal covering.
The uterus has 2 cavities what are they
Cavity of body
Cavity of uterus
Describe the cavity of body
It is slit like in sagittal section but triangular in coronal section with the apex of the triangle lying at the internal OS of cervix
Describe cavity of cervix
Also known as cervical canal.
The canal of the cervix is continuous with the internal OS.
The lower opening into the vagina is the external OS, circular in the nulliparous but after childbirth it becomes a transverse slit with an anterior and a posterior lip.
Position of uterus
It lies in the cavity of the lesser pelvis between rectum posteriorly and bladder anteriorly .
Describe anteflexion, ante version and retroversion of uterus
The adult uterus is bent forward on itself at about the level of the internal osto form an angle 70°, this is termed anteflexion of the uterus.
The axis of the cervix forms an angle of 90° with the axis of the vagina which is termed anteversion of the uterus.
In retroversion of the uterus, the axis of the cervix is directed upwards and backwards.
Relations of the uterus
Anteriorly -the body is related to the uterovesical pouch of peritoneum and lies on the superior surface of the bladder.
Posteriorly - lies the pouch of Douglas, with coils of intestine within it.
Laterally - the broad ligament and its contents.
Arterial supply of uterus
Uterine arteries which is a branch of internal iliac artery
Venous drainage
Uterine venous plexus formed by uterine veins
Drains into internal iliac veins
Lymphatics
Fundus and body drain into external iliac lymph nodes
Cervix drains into external and internal iliac lymph nodes
Wall of the uterus is formed by
Perimetrium – outer serous layer consisting of peritoneum supported by thin layer of connective tissue.
Myometrium– middle layer of smooth muscle which gets greatly distended during pregnancy.
Endometrium– Inner mucus later which firmly adheres to myometrium. Actively involved in menstrual cycle.
