Australia's Titmus still 'playing catch-up' for Paris Olympics

Olympic swimming champion Ariarne Titmus says she is still behind the curve with her Olympic preparations after a lay-off to have ovarian surgery.

Returning to competition for the first time since July at the Queensland state championships, Titmus came second behind world record holder Mollie O'Callaghan in Sunday's 200m freestyle final at the Brisbane Aquatic Centre.

The Olympic 200 and 400 freestyle champion said she was glad to get the surgery out of the way in September after doctors found benign tumours on her ovaries.

However, she said she had little time to waste ahead of defending her titles at the Paris Games starting in July.

"I'm really playing catch-up at the moment, trying to put in as much work as I can, so I'm pretty buggered racing here," she told Australian media.

"I know I'm on my way back and I can't read too much into my swims here.

"I definitely have time, but I don't have time to waste. I probably think I'm actually in a better position now than I thought I would be."

Titmus revealed she had successful surgery on social media in September, describing how she was "petrified" about losing the ability to have children before going into surgery.

On Sunday, she said she was "freaking out" at hospital after nurses asked for photos with her, and decided to go public with the surgery over concern it would be leaked elsewhere.

"I'd rather just put it out there and use it as an opportunity to create the conversation for people who might be going through the same thing," the 23-year-old told reporters.

"You never think when you go into hospital for an operation, and you're in your surgical gown, that people are going to ask you for a photo.

"That's what pushed me to say something, because I wanted to speak to it on my terms and not have it come out through someone else."