But some have found a haven.

After three years, the Nigerian woman summoned the courage to rebel, coaxed by a nun in Palermo who volunteered with a street unit that provides medical and psychological support to prostitutes. The nun passed on the address of a shelter in Caserta, just north of Naples, where the woman was able to hide from her handlers and break from her life on the streets.

Here at the shelter, known as Casa Ruth, the woman — who asked that her name not be used because her family in Nigeria does not know how she was earning her living — shares a tidy apartment in a modern building with a half-dozen other women, some of whom tell similar stories of debasement and imprisonment. They work together in a sewing cooperative run by the shelter called Newhope, whose goal is to equip the women with both confidence and skills.

“The cooperative is important because it shows them that they can produce, that they can make money not with their bodies, but through their creativity,” said Sister Rita Giaretta, one of the nuns at the Caserta safe house, where some 370 women — mostly from Nigeria — have found refuge in the past 20 years. “It is highly liberating.”

In cooperation with social workers, local institutions, and embassies, the nuns assist the women in getting new documents, necessary for a new start.

“Once they have documents, we tell them to walk with their heads held high,” Sister Giaretta said. As for the traffickers, she said, “They have to fear you, we tell them, you don’t have to be afraid anymore.”