cut in my vagina

I'm fairly sure this is my problem as well. Pantiliners and pads with tight pants, or in your case, horsebackriding, probably do not help. The pads absorb moisture, making the area dry, and we all know when something is dry, it it more likely to crack and split, like chapped lips. Try vaseline or diaper rash cream to help!

from the rubbing. There is a whole lot of that going on when you are riding a horse! It could also be a yeast infection. It is not likely that the pad itself cut you. You said that you have been tested for STD's, but are you sure you were tested for herpes? Most times herpes testing is not included when you request STD testing. Small cuts similar to paper cuts are a common symptom for women with herpes. It is often overlooked, because it is not what people commonly associate as being an outbreak. If you are sure your test results showed you were negative for type specific herpes testing, then it is probably just irritation. If not, you should get tested.

Horse riding in general can sometimes cause cuts in that area if you are hitting the saddle too hard, or in your case, the pad can definitely increase that problem. Next time you ride try not to wear such a heavy pad, or try a tampon, and also try to be a little more gentle and reduce the amount of bouncing going on while you ride.