So I have been with my fiance for awhile and we time to time attempt anal sex with her being the recipient. We both trust each other and understand both the positives and negatives to it. We use plenty of lube and she gets lined with desensitizer beforehand.

Whether or not its a long session or just a 1 minute penetration - she ends up with a fairly strong stomach ache for a long period of time.

I am curious on more seasoned recipients and their take on this. I have engaged in anal sex with 1 other partner and she didn't seem to really have this problem as far as I knew. She would get sore after awhile but not this. Thats only 1 person though.

Is this usually just part of it? is there some sort of trick to keep that from happening or something that you might know that could be making it worse?

The largest discouraging part is, that sometimes she can have a stomach ache for days. If we go about everything right it can be very enjoyable for both of us during, but I really want to minimize the after effects if we are to consider this as normal practice at all. Anyone have any ideas?