Official announcement here

Up Front Agency has just reported that Matsuura Aya has been diagnosed with endometriosis. She has had reoccurring abdominal pain for the past 4 years and finally went to see a physician about it. Due to the pain accompanied with this condition, Matsuura has decided to reduce her concert activities. After discussing with her, she has decided to continue working but in a limited sense so please continue to support her.

Update:
Comment from Matsuura Aya

To all you fans, thank you for your constant support.

I have something I would like to share with you.

This has been going on for about 4 years now. Every now and then, while in my every day routine, I would get stomach pains. After consulting with a physician, I was diagnosed with endometriosis. Upon discussing with my staff, I decided in 2009 to take a “2-3 year break from doing concerts”.

I continued to do research on my own and found that there are many others just like me who are suffering from the same condition. However, I found out that instead of treating the condition, they just ignore it and allow the condition to worsen. I hope that by sharing this I can help inform a lot of other women about this condition. If you are worried about the possibility of this at all, I highly recommend that you visit the hospital as soon as possible.

For me, these types of personal problems are a very delicate matter, so only people really close to me have known about this throughout my years of activity, however this year marks the 10th anniversary of my debut and is an important year for me and my fans. Despite hearing what everyone had to say, I can’t just stop everything though! Right ♥ So I will do my best to continue my activities without pushing myself too hard.

I apologize for making my fans worry.
I hope you can understand and please continue to support me from here on just like before.

Matsuura Aya