Kimberly Bell tearfully testified that the slugger also threatened to "tear out my breast implants because he had paid for them," and that he had admitted to taking the performance enhancing drugs during their nine year relationship.
Her explosive testimony prosecutor's say, proves that the former Giants star lied about steroid abuse during grand jury testimony in 2003, when the Bay Area Laboratory Co-Operative was being investigated.
The head of the company pleaded guilty to supplying pro athletes with the drug.
Bell told San Francisco's US District court that Bonds admitted to her
that he was using steroids when she asked him about an injury to his elbow.
She recalled: "He said it was because of the steroids, because it somehow caused the muscle and tendons to grow faster than the joint could handle, it sort of blew out."
She added that his testicles took an ‘unusual shape’ and that his sexual performance declined over their relationship and that he ‘had trouble keeping an erection.’
In evidence that prosecutors all claim prove steroid abuse she said that the ball player’s body changed shape and his mood shifted during over the time they were together.
"He was just increasingly aggressive, irritable, agitated, very impatient - almost violent. It was emotional and verbal to at one point physical," she told the court.
She added that Bonds grew and shaved off chest hair and developed acne on his back.
Bonds' attorney Cristina Arguedas attempted to paint former Playboy model Bell as an opportunist who profited off of their relationship.
She admitted that she received $100,000 from the magazine and did a number of interviews as well as inking a lucrative book deal.
San Francisco Giants clubhouse manager Mike Murphy took the stand and stated that Bonds needed a larger hat during the 2002 season.
Head growth is another side effect of use of human growth hormone.
Bonds is accused of four counts of making false statements and one of obstruction, but the home run record holder has pleaded not guilty to the charges that he lied to the court about knowingly using steroids.
The trial continues