I have the exact same problem, I cant understand what it is. I was convinced it was the IUD and got it removed but its bee 3 monthes and now I know it wasnt the IUD as im still going through it. The funny thing is its only on one side (right) its red, itchy and burns every time I pass water or take a shower or a bath. Iv also noticed it really plays up after i have had a shave. I have been to the hospital and thev carried out all tests, first they thought it may be genetal herpes I was so scared and worried as It just didnt make sense.... but they confirmed it came back negative but i re took the test just incase but im pitty sure its not.

Iv also noticed it gets really bad before and during my period! its so itchy and really burns... iv tried Depobase but it makes it itch even more! now im trying Betamethasone, but again I dont think its helping. I wonder can it be the shaving? its just gone from bad to worse! and its so embarrasing