From an interview with a former Iranian prison guard:
"In the Islamic Republic it is illegal to execute a young woman, regardless of her crime, if she is a virgin, he explained. Therefore a "wedding" ceremony is conducted the night before the execution: The young girl is forced to have sexual intercourse with a prison guard - essentially raped by her "husband." . . . "I could tell that the girls were more afraid of their 'wedding' night than of the execution that awaited them in the morning. And they would always fight back, so we would have to put sleeping pills in their food. By morning the girls would have an empty expression; it seemed like they were ready or wanted to die. "I remember hearing them cry and scream after [the rape] was over," he said. "I will never forget how this one girl clawed at her own face and neck with her finger nails afterwards. She had deep scratches all over her."