Branch 39 of the Supreme Court endorsed the ruling even though none of the flaws it previously cited as the basis for overturning her sentence have been resolved, Mohammadi's attorney Amir Raeisian said on Saturday.
"The Supreme Court was expected to once again overturn the ruling, but contrary to expectations, it did not," the lawyer said.
Mohammadi was convicted on charges of baghi or “armed rebellion against the state”, which carries the death penalty under the Islamic Republic's law.
Human rights groups say her membership in the Committee for Coordinating to Help Form Workers’ Organizations was the grounds for the death sentence.
The Islamic Republic's security forces consider the committee as an affiliate of the Komala, a Kurdish armed opposition group that has been engaged in guerilla warfare against the Islamic Republic. However, both Mohammadi's family and the Komala have dismissed any affiliation.
According to rights groups, during her detention, Mohammadi was deprived of basic prisoner rights, such as in-person visits and phone calls.
For a long time, she was denied visits with her family, especially her child, and was not allowed to contact them by phone.