The glass door was broken in the impact of the accidental hit and a damaged piece allegedly pierced her abdomen, police said.
The profusely bleeding woman was rushed to a nearby hospital but could not be saved, police said.
She was identified as Beena Jiju Paul from Cheranellur.
The woman hit the door when she ran out of the bank after completing her transactions there, police said.
Her body was later shifted to mortuary of the Ernakulam Medical College Hospital.
It will be handed over to her family after post-mortem on Tuesday, police added. TGB SA APR RAVINDRANATH APR RAVINDRANATH