Marion Jones has been sentenced to six months in prison after lying on oath about steroid use and cheque fraud.

US District Judge Kenneth Karas gave her the maximum sentence under her plea deal "because of the need for general deterrence and the need to promote respect for the law".

During today's hearing, Jones pleaded with the judge not to separate her from her children. "My passion in life has always been my family," Jones said. "I know the day is quickly approaching when my boys ask me about these current events. I intend to be honest and forthright and guide them into not making the same mistakes."

After long denying she ever had used performance-enhancing drugs, Jones admitted in October she lied to federal investigators in November 2003, acknowledging she took the designer steroid tetrahydrogestrinone (THG), also known as "The Clear", from September 2000 to July 2001. THG has been linked to Balco, a San Francisco Bay Area laboratory linked to the steroids scandal in sports. Jones sued Victor Conte, the Balco founder, after he repeatedly accused Jones of using performance-enhancing drugs and said he watched her inject herself.

Jones also admitted lying about her knowledge of the involvement of Tim Montgomery, the father of her son, Monty, in a scheme to cash millions of dollars worth of stolen or forged checks. Montgomery and several others have been convicted in that scam.

After entering her guilty pleas last year, Jones said: "It's with a great amount of shame that I stand before you and tell you that I have betrayed your trust. I have been dishonest, and you have the right to be angry with me. I have let my family down, I have let my country down, and I have let myself down. I want to ask for your forgiveness for my actions, and I hope you can find it in your heart to forgive me."

Jones' lawyers told the judge that she had been punished enough and should be sentenced only to probation, or perhaps be confined to her home. Prosecutors did not insist on prison time either, saying any sentence between probation and six months would be fair.

The sentence completes a stunning fall for the woman who was once the most celebrated female athlete in the world. She won three gold and two bronze medals at the 2000 Sydney Olympics.