What kind of inflatable do you use?

I have a very strong birth fetish. I love to experience that feeling so often i use my inflatable. I let it side slowly in me, pump it up, hold it in for a long time, accepting te feeling of pressure, wiggeling with my hips accept tje pressure, sometimes walking around in my house untill the moment i can't hold it anymore. Then i take a comfortable positions to push and while rubbing my clit i push until the inflatble get out. This is my 3th inflatable. The first one had a very round circale at the beginning so when the plug inside me it was anoying to my inner lips and it start to.burn. The second one was to round so i felt all the time pressure at my bladder, not a nice feeling. Now my new one like a watter ballon. Also round but the material is tinner. I was wondering what kind of model you use for vaginal births…

Lots of love Lavaa