Copyright 2008
Definition
The Mullerian duct anomalies are a group of congenital growth disorders, characterised by anomalies in the development, fusion, or septal regression of the Mullerian ducts.
The Mullerian ducts are precursors to the Fallopian tubes, uterus and upper two thirds of the vagina
Prevalence of the disorder is not known
The result has functional significancesince man are associated with infertility
Diagnosis is best accomplished with MRI or hystesalpingography.
Classification – American Fertility Society
|
I Hypoplasia/ agenesis |
II Unicornuate |
III Didelphys |
IV Bicornuate |
V Septate |
VI Arcuate |
VII DES |
|
Vaginal Cervical Fundal Tubal combined |
Communicating Non communicating no cavity No horn |
separate uterine bodies cervices and upper vagina |
Divergent horns with fundal cleft Bocollis or uncollis Complete partial At least 4cms separation between the horns >1.5cms fundal cleft |
Complete partial Failure of resorption of the central septum The septum may be muscular or fibrous To differentiate from bicornuate – the cleft is < 1.5cms |
mild concave on the fundal endometrial canal of no functional significance |
predisoposes to recurrent miscarriageor premature delivery T shaped uterus hypoplasia, irregular endometrial canal Predisposes to clear cell adenocarcinoma of the vagina |
Pathophysiology
failure of primordial ducts
failure of fusion of the primordial ducts
failed resorption of the septum between the two ducts
failed of structures that should normally resorb
Failure of primordial ducts
Mullerian agenesis is the most commomn abnormalityand results in complete absence of the vagina, cervix, uterus, and fallopian tubes
If one Mullerian duct develops and one is aplastic then a unicornuate uterus results which comprises of 20% of Mullerian duct anomalies.
Failure of fusion of the primordial ducts
Failure of fusion results in either a didelphys anomaly or bicornuate uterus
Didelphys is characterizewd by complete duplication resultinhgg in two hemi uteri, two cervices and two vaginas (septate).
Bicornuate uterus the failure of fusion only occurs in the body of the uterus so that there are two hemiuteri but there is a single cervix and a single vagina.
The small volume of the cavity that would house a prgnacy sometime prohibits full term pregnancy and preterm delivery may occur.
Failed resorption of the septum between the two ducts
The ducts may fuse but the septum between the ducts fails to resorb resulting in a single but septated corpus. Usually the vagina and cervix are single, but the uetrine cavity is variably divided
Failed of structures that should normally resorb