American Danielle Collins said suffering with endometriosis was "shocking" after winning her first match since March at the French Open on Sunday.
The 27-year-old needed surgery after being diagnosed with the condition in which tissue that usually covers the inside of the uterus grows outside of it.
Endometriosis is thought to possibly affect 10 percent or more of women and some of its causes are unknown.
It can cause pelvic pain and infertility, among other symptoms.
Collins told The Telegraph in an interview earlier this week that doctors removed "a cyst the size of a tennis ball from my ovary".
But she said the surgery had been a success, after beating Chinese qualifier Wang Xiyu 6-2, 4-6, 6-4 to reach the second round at Roland Garros.
"As most women in the world who have our menstrual cycles, I think it's something that sometimes when we're dealing with these painful moments, we learn to accept it," said Collins, who made the French Open quarter-finals last year.
"And for me things started to become too abnormal and really unhealthy, and it was causing a lot of havoc for me around that time...
"It certainly presented its challenges, but it's been really kind of shocking, like since surgery I've just felt so much better."
A lot of possible cases of endometriosis are never diagnosed, and Collins said she "kind of had some misdiagnoses along the way".
"(I) kind of thought that that was (a) normal (thing) to be dealing with," she added.
"I didn't realise that I would feel this much better after surgery, so I'm really relieved."
Collins hopes that speaking about her experience will encourage other women to seek help if in a similar situation.
"Sometimes there isn't a light at the end of the tunnel.
"So if I can ever be a friend to somebody and share my experience, hopefully that can offer them some knowledge or information that maybe they didn't know before.
"I was lucky to have a friend in my life that had endometriosis, and that helped me identify what I was dealing with. I think just being able to talk about it with other women is empowering."
The world number 50, a former Australian Open semi-finalist, will face Anhelina Kalinina in the next round, after the Ukrainian's 6-2, 6-4 win over three-time Grand Slam champion Angelique Kerber.
"I was very worried about overdoing it or doing too much too soon," Collins said.
"I think I definitely took my time and was very cautious, and so I think in the long run, that really benefited me because you definitely don't want to hurt yourself after undergoing surgery and all of that."