To anyone who has had this issue with labia or perineum tears and burning uncomfortable pain during sex, urination or sweating... Also can cause anal fissures (anal tears) I have had the same thing occur for over two years! I went from doctor to doctor and was checked for every STD imaginable. What I have found out has changed my life and finally given me freedom from this. I found out about systemic Candida and started eliminating yeast, sugar and a few other things from my diet. Many different things can cause it, such as being on antibiotics or stress. Sex seems to exacerbate it and you can pass it back and forth to your partner as they experience symptoms rarely and usually its anal itching. Google systemic candida and I guarantee you that if your doctors cant seem to find anything wrong that this will change your life and allow you to live a normal sex life again. I find that if I slip and start eating a lot of sugar even if its fruit that the systems will come back! Good luck to all who have this issue because it is truly debilitating.... Also apple cider vinegar diluted with water applied directly to the area or soaking with 1-2 cups of vinegar in bath tends to temporarily alleviate symptoms. Amazon has quite a few books on this subject that were extremely helpful!!