Gold standard investigation for septate uterus is
Septate uterus: Defined as uterus with normal outline and an internal indentation at the fundal midline Can be of two types- paial and complete Combined hysteroscopy and laproscopy help to differentiate between bicornuate uterus and septate uterus Ref: Shaw Gynecology 17 e pg 72.
HSG
Hysteroscopy
MRI
USG
Congenital malformations