Australian swimmer Brittany Elmslie has pulled out of this summer's World Championships in Russia after undergoing surgery on her breast.

The 20-year-old's coach Michael Bohl and Swimming Australia have advised Elmslie to withdraw from the meet after having a benign growth removed three weeks ago.

"I'm disappointed not to be able to be in Kazan and be part of another successful Dolphins team but I know I am not ready to give my best for the team and that wouldn't be fair on either myself or the team," Elmslie told Swimming Australia.

"I haven't been able to put in the training that's required to compete at that level and, after a lot of thought, I have decided that I am best to work through my health issues here in Australia and begin my preparation for the Olympic trials now.

"Swimming Australia and the people in my personal support group have been great in the last few weeks and I want to be able to repay their faith by being in the best shape possible in 2016."

Elmslie was selected to compete in the 4x100m and 4x200m freestyle relays.