Uterus II - Congenital Malformations
What percentage of women experience congenital uterine anomalies?
5%
Class III: Didelphys
A double uterus results from complete failure of two mullerian ducts to fuse together. Each uterus develops into a separate uterus each of which has a narrower than a normal uterus and only has one horn
How is the widening achieved when a uterus is fully developed and is wider at top than the bottom?
An expansion of the top part of the 'central wall'. As the wall grows, the tube becomes wider at the top forming the part of the uterus known as the "fundus."
What is similar to a septum uterus but considered a normal variant?
Arcuate uterus
What happens to the mullerian ducts during development?
At the end closest to the head of the embryo (top), these two tubes become fallopian tubes-remain separated at a distance. The other end of the tubes which are closest to the embryo's bottom lie side by side, close together and form the uterus by fusing together to become one structure
Infundibulopelvic ligament
Attaches ovary to the lateral pelvic wall and contain the neruovascular bundle
Hematometrocolpos
Blood-filled vagina and uterus
How do congenital uterine anomalies occur?
Defects in paired mullerian duct development, fusion, or respiration.
What happens when a class III: didelpys is complete?
Duplication of uterus, cervix, and vagina. 2 fundi, 2 cervix, 2 agina. Not usually associated with fertility problems
What happens in class IV: Bicornuate Uterus?
Duplications of the uterus, sometimes cervix. It's the most common uterine anomaly. Results from failure of mullerian duct from the top.
Class II: Unicornuate
Failure of the development of one half of the uterus May be associated with a rudimentary horn from the contralateral duct Related to infertility and pregnancy loss
Hydrometrocolpos
Fluid-filled vagina and uterus
What is a partial bicornuate uterus?
Fusion between the mullerian duct occurs at the bottom, not at the top- results in a single uterine cavity at the bottom with a single cervix but it branches into two distinct horns at the top.
Class I: Agenesis or hypoplasia: segmental or complete
Incomplete vaginal canalization, transverse septum or vaginal atresia. Young girl reaches puberty without menstruation.
Where does the right ovarian vein drain?
Into IVC near renal vein
Where does the left ovarian vein drain?
Into left renal vein
What are the fallopian tube divisions?
Intramural, infundibulum, isthmus and ampulla
What are the three subcomponents of the broad ligament?
Mesometrium, the mesentery of the uterus; largest portion of the broad ligament Mesosalpinx, the mesentery of the fallopian tube Mesovarium, the mesentery of the ovaries
What secretes estrogen?
One or more mature follicles surrounding mature oocytes
Fimbria
Ovarian fimbria attaches to vary
Where does ovulation occur?
Peritoneal cavity
What happens in a class VII; DES related?
Related to exposure to drug Diethlystilbestrol (DES) in utero, T shaped cavity with irregular contour. Daughters of mothers who were exposed to DES during pregnancy are predisposed to uterine abnormalities, 2/3 have small, incomplete formed uterus, t shaped cavity, or 1/2 have cervical defects.
Corpora lutea
Remains of follicle after ovulation, secretes estrogen and progesterone.
What is a partial septate uterus?
Resportion of the lower part of the median septum, but the top of the septum fails to dissolve. There is a single cervix and uterine cavity at the bottom but at the top that cavity divids into 2 distinct horns.
What is a complete bicornuate uterus?
Results in a two seperate single horn uterine bodies sharing one cervix
Ovarian ligament
Runs within broad ligament form inferior medical pole of each ovary to the uterus in vicinity of cornu
How are ovaries measured?
Sag, trans, and AP
Corpora albicantia
Scars of regressed corpora lutea
Which class has the highest incidence of fertility problems?
Septum uterus
How does the uterus form?
Structures which give rise to the uterus are a pair of tubes called mullerian ducts
What is the internal structure of the ovaries?
The cortex, functional part. Medulla, contains connective tissue and vasculature
What kind of procedure can help with a septum uterus?
The septum may be hysteroscopically removed
What happens in a class VI: arcuate uterus?
The uterus is esentially normal in shape with a small, midline indentation in the uterine fundus. Results from failure to completely dissolve the median septum, does not seem to have any negative effects on pregnancy.
What happens in a class V: septate uterus?
Two mullerian ducts fuse normally, there is failure in degeneration of the median septum.
What are the US findings for a class II: unicornuate?
Uterus long and slender (cigar shaped), deviated to one side
How do you get the volume of ovaries?
Volume = sag x AP x Trans / 2
What is a complete septate uterus?
When a median septum persists in the entire uterus separating the uterine cavity into two single-horned uteri which share one cervix
Ovarian arteries
arise from the aorta near renal arteries and run inferiorly in suspensory ligament and mesovarium
Mesovarium
attaches each ovary to broad ligament
Hydrocolpos
fluid filled vagina