The 23-year-old is scheduled to return to Spurs in January but the deal could be extended if the two clubs agree to let hims tay.
O’Hara has impressed during his time at Fratton Park.
“We’ll wait and see on Jamie,” said Spurs boss Harry Redknapp.
“If we’re OK and we’ve got plenty of bodies and Jamie wants to stay and they want to keep him on loan, then something could be done.”