The disgraced former doctor is currently serving a jail term of up to 175 years.

He appealed to the sixth US Circuit Court of Appeals in Cincinnati, claiming that the district judge presiding over his case had wrongly increased his sentence based upon his multiple sexual assault convictions.

His lawyer argued the judge had erred in calculating the sentence for possessing 37,000 images of child pornography.

Nassar had pleaded guilty to criminal sexual misconduct, possessing child pornography and then trying to destroy the files after learning he was under investigation.

The appeal against the sentence was turned down by a three-judge panel.

Nassar is also appealing against state sentences of between 40 to 175 years and 40 to 125 years for criminal sexual misconduct.

He has challenged the length of both sentences.

The former doctor has also requested the sentences run concurrently, rather than consecutively.

Nassar is reportedly staying in a Federal transfer facility, after he was allegedly assaulted after being released into the medium-security Tucson prison.

More than 250 people accused him of abuse including numerous top gymnasts.

The crisis has led to fierce criticism of both USA Gymnastics and the United States Olympic Committee over what they knew and when and whether they could have prevented the abuse.

Last month, United States Senators questioned the sincerity of reforms introduced by both organisations after they each made court filings seemingly trying to absolve themselves of blame.