The room had no toilet and stank of faeces and urine, police reportedly said.
But she was said to have been freed this month after an anonymous tip-off led police to the property in the town of Uruburetama – breaking through padlocks at the building to find the woman.
A police spokesman reportedly: “She rushed over to the officers with open arms when she saw us.”
The main family members responsible were her unnamed father and brother João de Almeida Braga, 48, who was arrested for illegally detaining his sister and mistreating her.
While the dad was not apprehended due to ill health, her mother is believed to have tried to resist the punishment for her daughter.
When she gave birth, she was said to not have been able to keep the baby and as the brother and father gave the child away.