Australian swimming champion Ariarne Titmus has had surgery to remove benign tumours from an ovary.
The women's 400 metres freestyle world record holder discovered the tumours by chance when having an MRI scan on a sore hip.
The Olympic and world champion feared implications from the tumours would deny her a chance to be a mother, something she described as her "biggest dream".
But Titmus said she now felt blessed that surgery on Thursday successfully removed the tumours.
"For a while I've been managing an ongoing hip injury and three weeks ago I had an MRI to suss out exactly what was going on," Titmus posted on Instagram on Friday.
"Sure enough, there was a little something with the hip that is completely manageable.
"However it was something else that the doctors picked up on that made everything else seem irrelevant.
"A large growth was found on my right ovary.
"For anyone that knows me, they'd know I'd give up anything in the world to be a mother, it's my biggest dream so this was a scary time for me.
"Of course in these moments you think of the worst case scenario and I was petrified of potentially losing the ovary or there being implications that could affect me and my desire to have children one day.
"However, I am one of the lucky ones."
Titmus said her right ovary contained two benign tumours, each four centimetres in size, called dermoids.
"Yesterday I had surgery and they were removed safely," Titmus said.
"I'm feeling well and relieved they are out.
"Being an athlete is tough. Being a woman is tough.
"In the past month I've learnt more about my body and what it is capable of.
"I've learnt that being fit and healthy doesn't mean you're immune to these things.
"I feel blessed that I found these tumours before they got even bigger and started to have real implications on my health."
Titmus, who looms as a star attraction at the pool at next year's Paris Olympics, said she would now rest and recover "for a couple of weeks" before returning to training.