I joined Susans to ask about the same thing. I realized in January through lack of dilation that my vagina had shortened and narrowed; if I stretched my legs I would feel the stretch inside and I never used to feel that before. I also could only fit the smallest dilator in and it only went to the first dot. I wasn't concerned about the width cos I knew from experience that this can easily change, but the lack of depth scared me. I also measured myself incorrectly -- I thought it was only 3 inches to the first dot because i measured from the inside of the curve and not from the outside of the curve which is how it was supposed to be. So I started out post-op at 5 1/2 inches with the smallest dilator and now it was down to 4 inches.
So I started dilating EVERY DAY and often for several hours a day. Now I am eleven years post-op and the skin is quite healthy inside and I knew from the past that I could dilate while sitting in a chair at my computer while pressing the end of the dilator on the chair seat; I know that this is NOT a good idea for those newly post-op or with certain issues, but I know that this worked fine for me and that I could keep steady pressure on the apex by doing it this way. So I started that in early January and now it is May. When I measured myself again in early April, I was very surprised to see that I was now a hair under 5 inches. So I had regained an inch in three months. A big part of this also was my use of Estrace cream every day which definitely helps my skin become more flexible. And then on Monday just before my pelvic exam, I dilated and measured again and saw that now I have a depth of just a hair under 5 1/2 inches with the smallest dilator. So essentially I am back to my original depth. The width of course was rather easy to regain, just as I have in times in the past. I ordered the largest #5 size dilator and it went in easily even though I never before used a dilator that big. So I have been pretty heartened by this experience, because I had feared that I had lost the depth for good. But it has taken a lot of work, and I know it will continue to take work to maintain it. Oh yeah, and in the pelvic exam my doctor tells me that the tissue still looks very healthy, well estrogenized, and free of problems on the inside.