Jeff - I think I can safely speak for everyone when I say there is no way any of us women are going to pee in the shower!!
Warning: fairly explicit post. Roberta, Sorry, not to be argumenative, I love your posts, but I'm fessing up, I know many women, including myself, who would pee in the shower, and here is why.
As a labor and delivery room nurse, as well as a Lamaze instructor, there are many reasons I suggest peein' in the shower, all of them involving pain! After delivery and an episiotomy, or if you have small tears in the front of the birth canal that are too small to bother with stitches, the first couple of pep-pee times can be really uncomfortable in the stinging category. If you pee in the shower, it mixes with water and the sting factor goes way down. The tears in the front are right where the pee comes out (by the urethrea for you technical folks) and much more prone for stinging with peeing than a regular episiotomy is (but on the up side they are much smaller, heal faster and don't get irritated or scar like the epis does).
Other reasons to pee in the shower with water (!) include yeast or other infections, or for us over 50 folks, early menopause symptoms with loss of estrogen that makes vaginal tissues thinner, and urine irritates these sensitive tissues and mixing with water to dilute makes it less difficult and less of an uncomfortable situation! (especially after S-e-x). Let me guess, the boys are reading again!:lol:
Lastly, if you are having trouble starting to "go" , for example, after surgery, or if you are overfull, or you know it will hurt if you do, the warm water over your body (boys, go away right now, stop reading) can help with the release process. Think of the old adolescent camp trick of putting a person's hands in warm water to make them pee the bed, or your baby pee'ing every time you put him or her in the bathtub. yup, we also recommend peeing while sitting in a tub of warm water (then draining the tub of course, not bathing in it!)
Remember, unless you have a urine infection, urine is sterile, and since you have both water and presumably soap in the shower as well, you are basically washing it right down the drain, into the same place as what comes out of the toilet. I am assuming, of course, as a female, you are pretty much close to the drain, unlike a male who could be shooting for the wall! There may be an "ick" factor, but you are not making your shower a toilet. I am not recommending you replace your toilet with a shower full time, and certainly not a public shower
. But occasionally, at home, with proper cleaning techniques, it's really not so icky. For me, icky trumps pain anyday! 
Debbie, over 50, mother of 2, school nurse.
Haven't tried the latter yet! 
