The announcement that Safiya Husseini's death sentence had been overturned set off celebrations among women's advocates and others who had protested her planned execution under the Islamic laws of Sokoto state.
An Islamic court condemned Ms. Husseini to death by stoning last October after she gave birth to a child, years after she divorced her husband. Under Sokoto's Sharia law, a divorced woman who has sexual intercourse and conceives a child out of wedlock commits adultery.
Ms. Husseini initially said she became pregnant when she was raped by a neighbor.
But when her attorneys appealed her case in January, they said Ms. Husseini, who is illiterate, had misunderstood her interrogators' questions. They said the man with whom she had conceived her child was her former husband. Under the Islamic code, having sexual intercourse with a former husband would not constitute adultery.
In arguing their appeal, attorneys said the court had committed serious procedural errors.
Ms. Husseini's case triggered an outcry among international women's and human rights groups, especially in Europe.
Abiola Akiyode-Afolabi heads the Safiya Must Not Die Campaign, based in Nigeria's main city, Lagos. She tells V-O-A she believes the Islamic court's decision Monday will set a precedent that will benefit all Nigerian women.
"It would have been an embarrassment (for) the Nigerian government if they had gone ahead and stoned Safiya to death. Because we are in a democratic setting, it would be better for everyone in Nigeria to respect international norms and standards rather than violate human dignity. So, I think it is a big lesson and it's a plus for Nigerian women that we have been able to uplift the rights of women, and that we did not allow injustice to thrive".
The announcement of Safiya Husseini's acquittal came as reports from northern Katsina state said yet another woman, Amina Lawal, had last week been sentenced to death by stoning on similar charges. Women's advocates say they hope the outcome of the Husseini case will help overturn Ms. Lawal's sentence and discourage future sentences of this type.
Last week, Nigeria's justice minister published a letter declaring Sharia unconstitutional. The minister called for governors of states that had adopted the Islamic code to modify their application of it to conform with Nigeria's secular laws.
The justice minister said he made the appeal, fearing that further publicity surrounding Sharia punishments might cause Nigeria to be isolated from the international community. Islamic leaders protested, saying the minister's statement amounted to discrimination against Muslims.
The imposition of Sharia in 12 of Nigeria's predominantly Muslim northern states has strained relations between the country's Muslims and Christians. The implementation, which began two-years ago, has triggered ethnic and religious clashes that have killed thousands.
President Olusegun Obasanjo, a southern Christian, has said he opposes the implementation of Sharia, but has not been able to stop its enforcement. Nigeria's constitution allows the states to adopt their own legal codes.