Bicornuate uterus is classified as a class IV Mullerian duct anomaly. It's characterized by fundal clefting that may extend to the cervical canal (Bicornuate Bicollis) or the level of the internal os with one cervix (Bicornuate Unicollis).

Differential diagnoses include a septate uterus in which there is no external clefting but show a flat uterine fundus with an internal septum and uterine Didelphis in which there is a complete failure of Mullerian fusion.