The Guardian
·26 March 2026
‘Trust your own feeling’: Everton’s Katja Snoeijs on her endometriosis diagnosis

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Yahoo sportsThe Guardian
·26 March 2026

When the sharp, stabbing pain in her abdomen became so severe that she had to be substituted at half-time during an Everton match, Katja Snoeijs knew what she was experiencing was not merely “normal period pains”. And she was right.
The 29-year-old Netherlands striker has since been diagnosed with endometriosis, which affects one in 10 women. She says she counts herself lucky, because she received her diagnosis within a year and was shocked to learn the national average wait for a diagnosis in the UK is nine years.
The condition involves cells similar to those found in the lining of the womb growing elsewhere in the body, which can lead to inflammation and chronic pain. This year, Snoeijs had keyhole surgery to treat it and, having recovered to resume full training before Saturday’s Merseyside derby with Liverpool in the WSL, has decided to open up about her experiences in the hope of encouraging more women to seek help.
Snoeijs, who has played for Everton since 2022, spoke exclusively to the Guardian and recalled being unable to stand up straight during a match when her symptoms came on strongly. “Probably since I was a teenager, I had symptoms around my period, but back then I was like: ‘Oh, it’s normal period pain,’” she says. “But in the last two years, it would also impact me on the football pitch. There was one national team session where mid-session, I couldn’t run, I was in so much pain. I felt like I had to throw up and I had to leave the session. But even then, it was so hard to acknowledge something was not right.
“Then here at Everton, there was a game last season where I got my period and I tried to push through. I was starting that game, but walking out, I couldn’t stand up straight, so I took a lot of pain medication. But at half-time, I had to be subbed off because of the pain. That was the moment where I was like: ‘I need to do something about it.’
“It’s a little bit hard to predict. Whenever it’s there, it goes from zero to a hundred. It’s like a very sharp stabbing pain in your abs. As an athlete, it’s always hard to acknowledge when you feel something. It’s natural to ‘push through’. In your head you’re thinking: ‘Oh I can still do something’ but you’re only making it worse for your body. I didn’t want to be weak, so I wanted to try to push through, help the team [but I couldn’t] physically run any more.”
The worst experience she had away from the pitch came this Christmas. “Suddenly I could feel the cramps, something was wrong,” she says. “The next three days I had to just lay in bed because I was in so much pain. A lot of women either get told it’s ‘normal period pain’ or you think it yourself. But we all know it’s not normal to lay in your bed for three days because of period pain.”
March is Endometriosis Action Month and Snoeijs says since first writing about her condition in a post on social media two weeks ago, it has prompted more, helpful conversations even within the Everton dressing room: “Everyone has been really nice and supportive. In our changing room, it opened up conversations about period pain and I know there are other teammates as well that have been struggling. It’s helping us to understand each other better.”
Last season, Snoeijs sought help via the club doctor and private gynecologists, and after one gynecologist initially appeared unconcerned by her symptoms, a second opinion led to her having an MRI that indicated her endometriosis, and she was recommended to undergo a laparoscopy. But having the surgery was a tricky decision, in the middle of her career. She said: “I had this chat with the team doctor and he said: ‘Whatever you want to do, we’ll support you in it.’ We went through different scenarios and decided that it would be best to do it as quickly as possible.
“It went really well. They found a little bit more endometriosis than expected, but they were able to burn as much as possible away. Initially I just needed to recover from the general surgery, the anesthesia, and just the scars. But once that settled down a little bit, my recovery went really smoothly.”
It took around a year to see her diagnosed – most women wait at least nine times longer. “It’s actually crazy that it takes so long to get the right diagnosis,” she says. “Hopefully just talking about it more will help women to understand that their symptoms are not normal and encourage them to go to the GP.”
Emma Cox, the chief executive of Endometriosis UK, told the Guardian: “We’re incredibly grateful and thankful for Katya for speaking out. To have someone of her calibre talk about a disease like endometriosis really makes a difference to people. For elite sports people, endometriosis can be really challenging, because, of course, you can’t change the fixture date or the dates of a national tournament.
“Whilst period pain is normal, if that is interfering with your day-to-day life, we’d say go and seek help from a doctor and the common symptoms are pelvic pain, heavy period pains, heavy menstrual bleeding, painful bowel movements, pain when urinating, pain during or after sex, difficulty getting pregnant, and fatigue when you’ve got one or more of the other painful symptoms.”
Snoeijs has shown resilience to overcome medical hurdles throughout her life and career. Born with a hole in her heart and growing up with one leg longer than the other, her early life was not easy, seeing her go through several major surgeries as a child.
“It makes me proud to think what I was able to reach with those kind of challenges,” she says. “And hopefully that will just motivate people that go through the same.”
After recovering from her latest surgery, she is now focusing on Saturday’s showdown with Liverpool at Goodison Park. Their rivals got the better of them in their most recent meeting, in the FA Cup. “We’re all really motivated. [After] the last derby, the FA Cup game, we all feel like that was not our best game and that we have something to set right. And the derby is always special.”
There is a bigger public health focus on her mind, though, as she concludes with a passionate message to any women who think they might have endometriosis: “Trust your own feeling and your own body. We as women are really good at understanding ourselves. Try to be confident and don’t let yourself be pushed away if you feel like you’re not being heard or not getting the right treatment. Even with a condition like this, it doesn’t need to impact your sport career. You can still play at the highest level.”
Header image: [Photograph: Christopher Thomond/The Guardian]









































