The Common Vein  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