The teenagers were rescued from the Gally Gally hotel on Monday in the southeastern state of Anambra, where they were used "for sex slaves, prostitution and baby factory," state police spokesman Tochukwu Ikenga said late Wednesday.
Four of the girls were pregnant, he said, while some weapons and cash were recovered from the hotel.
Ikenga said investigations were ongoing while the girls would be handed over to the government agencies for rehabilitation.
He said the owner of the hotel was on the run, while three suspects had been arrested.
"All suspects will be charged to court at the end of investigations."
Nigerian police have previously freed dozens of under-aged women and babies from illegal maternity homes known as "baby factories" where women are forced to have children for sale on the black market.
The so-called "factories" are usually small illegal facilities parading as private medical clinics that house pregnant women and offer their babies for sale.
In many cases, young women have been held against their will and sexually assaulted before their babies are sold on the black market.