Mullerian Duct Anomalies

MULLERIAN DUCTS:

• Paired ducts derived from intermediate mesoderm
• Known as paramesonephric duct.
• Mullerian ducts form as buds of coelomic epithelium .
• Grows downward & lateral to corresponding wolffian ducts.
• Turn inwards & crosses anterior to it joining its fellow from opposite side.
•  Structure developing from Mullerian duct in males is Prostatic utricle

PARTS:

• Upper vertical part lateral to wolffian duct → fallopian tube.
• Middle horizontal part crossing wolffian duct → remaining part of fallopian tube.
• Lower vertical part fusing to opposite part → uterus, cervix, upper 1/3 rd of vagina.
• In forming the uterus, the mullerian ducts fuses from below upwards

MULLERIAN DUCT ANOMALY CLASSIFICATION:

In complete mullerian duct aplasia  Fallopian tubes, Uterus & Vagina are likely to be absent.

 46 XX karyotype

It is a seven point system that can be used to describe a number of embryonic Müllerian duct anomalies:

class I: uterine agenesis / uterine hypoplasia

1.  vaginal (uterus: normal / variety of abnormal forms)
2.  cervical
3.  fundal
4.  tubal
5.  combined

class II: unicornuate uterus/unicornis unicollis, ~15% (range 6-25%)

1.  communicating contralateral rudimentary horn contains endometrium
2.  non-communicating contralateral rudimentary horn contains endometrium
3.  contralateral horn has no endometrial cavity
4.  no horn

class III: uterus didelphys, ~7.5% (range 5-11%)

class IV: bicornuate uterus: next commonest type, ~25% (range 10-39%)

1.  complete division, all the way down to the external os (bicornuate bicollis)
2.  partial division, not extending to the internal os (bicornuate unicollis)

class V: septate uterus: commonest anomaly, ~45% (range 34-55%)

1.  complete division, all the way down to the internal or external os
2.  incomplete division, involving the endometrial cavity but not the cervix

class VI: arcuate uterus, ~7%

class VII: in utero diethylstilbestrol (DES) exposure (T-shaped uterus)

MULLERIAN DUCT ANOMALIES CHARCTERISTICS:

• Mullerian agenesis shows Normal breast development but  Fallopian tubes, Uterus & Vagina are likely to be absent
• Androgen Insensitivity Syndrome is associated 

Uterine agenesis:

• Complete absence of uterine tissue above the vagina. 
• Primary amenorrhoea, with normal hormonal levels guaranteed by fully functional gonads.

Unicornuate uterus:

• Second most commonly associated with miscarriages. 
• Common on right side
• Associated with renal anomalies, cryptomenorrhea & primary infertility

Uterus didelphys:

• Complete duplication of uterine horns as well as duplication of the cervix, with no communication between them.  
• Complete failure of mullerian duct fusion
• Mostly asymptomatic 
• Dyspareunia may be seen as result of vaginal septum

Bicornuate uterus:

• Early pregnancy loss and cervical incompetence
• Incomplete fusion of paramesonephric duct
• Associated longitudinal vaginal septum, abnormal renal tract
• The most important indication for surgical repair of a Bicornuate Uterus is Habitual abortion

Septate uterus:

• Increased rate of pregnancy loss. 
• Most common congenital abnormality of uterus

Arcuate uterus

• Least commonly associated with reproductive failure

T-shaped uterus:

•  Most commonly associated abnormality from in utero diethylstilbestrol (DES) exposure

DIAGNOSIS:

Hysterosalpingogram:

• Unicornuate uterus: Fusiform shaped endometrial cavity tapering  apex and draining into a single fallopian tube
• Uterus didelphys(IOC): 2 separate endocervical canals open into separate fusiform endometrial cavities, without communication between the two horns. Each endometrial cavity ends in a solitary fallopian tube.
• Bicornuate uterus: Divided uterus
• Septate uterus:  An angle of less than 75° between the uterine horns is suggestive of a septate uterus, and an angle of more than 105° is more consistent with bicornuate uteri.
• T-shaped uterus :Opacified endometrial cavity appears , with a shortened upper uterine segment, resulting in the characteristic T-configuration.

Other diagnostic test:

• MRI:Imaging modality of choice for septate uterus
• RADIOGRAPH
• Ultrasound:Important in Uterus didelphys & Septate uterus

 Exam Important

Don’t Forget to Solve all the previous Year Question asked on MULLERIAN DUCT ANOMALIES