Chinese coach Lu Shanzhen told The Associated Press they gave the FIG new documents on Thursday to try to remove any doubts about He's age, including an old passport, residency card and her current ID card.
Lu said all the documents were issued by various departments of the Chinese government, and that he had nothing more to put forth as evidence.
"If these valid documents are not enough to clarify this problem, then what will you believe?" an indignant Lu said.
The FIG has said repeatedly that a passport is the "accepted proof of a gymnast's eligibility," and that China's gymnasts have presented ones that show they are age eligible. The IOC also checked the girls' passports and deemed them valid before the games began.
Andre Gueisbuhler, secretary general of the FIG, said the federation would release a statement later Friday.
"For the time being, there is nothing I can add," Gueisbuhler said.
A gymnast must be 16 in an Olympic year to compete at the games. But questions about the ages of at least three of the athletes have persisted. Online records and media reports suggest three Chinese gymnasts - He, Yang and Jiang Yuyuan - might be as young as 14.
The IOC said previously that it had verified the passports of all athletes competing at the games.
"We are not in a position to say 'It's good, it's not good.' It's a government document," FIG president Bruno Grandi said earlier this week in an interview with the AP.
The IOC did not give details on what new information prompted it to act now, three days after the gymnastics competition ended.
"With some questions still remaining, we asked the federation to take a closer look," Davies said.
The Chinese women won six medals, including the team gold and He's gold on uneven bars. Media reports include a Nov. 3 story by the Chinese government's news agency, Xinhua, that suggest He is only 14. Asked earlier this week about her age again after winning the uneven bars title, beating American Nastia Liukin in a tiebreak, she said:
"I was born in 1992, and I'm 16 years old now," He said. "The FIG has proved that. If I'm under 16, I couldn't have been competing here."
Earlier this month, the AP found registration lists previously posted on the Web site of the General Administration of Sport of China that showed both He and Yang were too young to compete. He was born Jan. 1, 1994, according to the 2005, 2006 and 2007 registration lists. Yang was born Aug. 26, 1993, according to the 2004, 2005 and 2006 registration lists. In the 2007 registration list, however, her birthday has changed to Aug. 26, 1992.
"We played fair at this Olympic Games," Liukin's father and coach, Valeri, said after they arrived back in the United States. "... If somebody cheated, shame on them."
Added Steve Penny, president of USA Gymnastics: "USA Gymnastics has always believed this issue needed to be addressed by the FIG and IOC. An investigation would help bring closure to the issue and remove any cloud of speculation from this competition."
Age falsification has been a problem in gymnastics since the 1980s after the minimum age was raised from 14 to 15 to protect young athletes from serious injuries. The minimum age was raised to its current 16 in 1997. Younger gymnasts are considered to have an advantage because they are more flexible, and are likely to have an easier time doing the tough skills the sport requires. They also aren't as likely to have a history of injuries or fear of failure.
North Korea was barred from the 1993 world championships after FIG officials discovered Kim Gwang Suk, the gold medalist on uneven bars in 1991, was listed as 15 for three years in a row. Romania admitted in 2002 that several gymnasts' ages had been falsified, including Olympic medalists Gina Gogean and Alexandra Marinescu.
Even China's own Yang Yun, a double bronze medalist in Sydney, said during an interview aired on state broadcaster China Central Television that she was 14 in 2000.
"It's not just me. The parents of our athletes are all very indignant," Lu said. "They have faced groundless suspicion. Why aren't they believed? Why are their children suspected? Their parents are very angry."