A former prison doctor for the US Penitentiary in Atlanta has pleaded guilty to sexually abusing three male inmates.

The abuse occurred in October 2011 when the three men sought medical treatment, according to the Atlanta Journal-Constitution.

The former physician, Lewis Jackson, 36, pleaded guilty to sexually molesting the inmates on Monday and is due to be sentenced in February 2013.

He tried to perform oral sex during physical examinations and also tried to have anal sex with one inmate, the AJC reports.

Mr Jackson appeared in court with his wife and parents.

He faces a separate charge, which is still pending, in Washington for allegedly molesting an inmate at the District of Columbia jail in 2008.

Mr Jackson was initially scheduled to enter his guilty plea in August but that was delayed because he tried to commit suicide the previous day.

He was then hospitalised for seven days.