The actress visited the red-light district in Calcutta to shoot upcoming U.S. TV documentary Half the Sky, based on Nicholas D. Kristof's book of the same name.
Ferrera visited a local school and met with officials at the New Light charity, who work to provide education and protection for women and children at high risk.
Kristof, who accompanied Ferrera, says, "America (met) with a terrific 10-year-old girl who has studied English with the help of New Light and wants to be a doctor. Most of the girls in the area get little or no education and follow their mothers into prostitution. America was terrific to work with on the (TV network) PBS version of Half the Sky."