Independent consultant Patrick Carter is due to review the Wembley National Stadium project and the Lee Valley athletics stadium, designed by FaulknerBrowns. He has seven weeks to make his report.
Jowell said: "Sport England needs to assess whether the Lee Valley project can be funded and managed in its current format, and if not, what alternatives might be viable."
Jowell ruled out staging athletics at the 90,000-seat national stadium at Wembley or at the 18,000-seat Crystal Palace.
A spokesperson for the Department for Culture, Media and Sport indicated that the Lee Valley stadium is the only alternative under consideration.
"Patrick Carter will look at what changes need to be made to make it work," she said.
Jowell also announced an £80m package to cover a shortfall for staging the Commonwealth Games in Manchester next year.