The passage through the 'sensitive part' is painless, the pain is during the passage through the ureter, the tube from the kidney to the bladder. I think that's the same in men and women. Perhaps I'll get a sex change operation and settle the matter once and for all.
This confirms what my doctor says. He insists the pain comes from it temporary blocking urine from passing through the ureters. He says without the blockage, you would not feel anything, which is why I do not feel most of my stones. I have large ureters and thus the stones can pass through them with ease.