The alleged incidents occurred two years ago when Sterger and Favre were both with the Jets in 2008.
The allegations against the 41-year-old Minnesota Vikings quarterback surfaced in October on the website Deadspin.
A three-time league MVP, Favre has consistently refused to answer reporters' questions about the allegations. He said early on that he had enough to worry about with the Vikings' next opponent, and that's certainly been true this season.
Convinced to come back for one more run at a title by three Minnesota teammates who flew down to see him in Mississippi, Favre's second year with the Vikings has been nothing like the charmed run of last season, which ended with a heartbreaking loss to New Orleans in the NFC championship game.
The Associated Press contributed to this report.