Christian charity Middle East Concern said Mahrokh (Roksare) Kanbari was convicted of "propaganda against the system" after a hearing at Karaj Revolutionary Court on 27 July.
She was initially arrested shortly before Christmas 2018, when three agents from Iranian intelligence raided her home and confiscated mobile phones, Bibles and other Christian materials.
Kanbari endured ten days of intense interrogation before her conditional release on submission of bail of 30 million Toman (approximately £2,000).
US Vice President Mike Pence appealed for her acquittal in a Tweet on 2 August, writing: "I am appalled to hear reports that Iran's despotic rulers have punished yet another Christian woman for exercising her freedom to worship. Iran must free Mahrokh Kanbari today. Whether Sunni, Sufi, Baha'i, Jewish or Christian, America will stand up for people of faith in Iran like Marokh."
Kanbari's friends have asked Christians to pray that "the Lord will use politicians and human rights defenders around the world to speak up for religious freedom and the Iranian authorities will stop harassing, arresting and imprisoning religious minorities in Iran".
They also have asked that Christians will be inspired by the example of Kanbari and others to "stand firm in the faith for the sake of Jesus Christ".
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