Kishori Yelankar found some live rounds dumped near her house in Kisan Nagar on Sunday night, but mistook them for chocolates, her father said.
Kishori was rushed to a hospital in suburban Kalwa and doctors their tried to take the cartridge out.
Dr Sukesh Thakur of the Shivaji Civic Hospital said today that the round came out in the natural course.
He said it had not caused any damage to the girl's abdomen.
Till filing of this report, no police case is filed in recovery of cartridges.