Tom Moore, a spokesman for the school, said the math department TA attached the nude pictures to an email sent to 28 pre-calculus students instead of the solutions to some math problems, the Iowa City Press-Citizen reported Thursday.
Moore said he could not speculate on any consequences that could result from the investigation.
"Ultimately, as a student, any discipline [if it occurs] would be non-public under [the Family Educational Rights and Privacy Act]," he said.
Some students sympathized with the TA, whose name has not been released.
"This just goes to show that you have to double-check before you hit 'Send,'" said journalism student Kristina Gonzalez, 21. "I feel bad for her, but once it got out, there was no chance of stopping it."
However, some said they believe the TA should face harsh consequences.
"I think she should be fired," said computer science student Tim Miller, 22. "It was completely unprofessional."