Lt. Cmdr. Rebecca C. Dickinson, 38, told the jury she worked for Deborah Jeane Palfrey's escort service for six months, using the name "Renee" while having sex for money, The Washington Post (NYSE:WPO) reported. She said she quit in 2006 partly because of "other responsibilities."

Palfrey is on trial for racketeering, money laundering and using the mail for illegal purposes.

"It was getting harder for me to do," Dickinson testified. "I had other responsibilities. I didn't like it. I quit for many reasons. Partly because of other commitments."

Dickinson, who worked as a supply officer at the academy, enlisted in the Navy in 1986 and was commissioned an officer in 1993 after graduating from Auburn University. She was the 13th admitted former call girl to testify since Tuesday in the government's case against Palfrey. Three former clients of the escort service also have testified.