Yes, not being inclined to do sex at all is very common with aspies.
Or is it "normal" for AS already? At least in the sense that you have not to feel strange about it or that you have to change - its just what you are supposed to be?!
I hosted a discussion group of aspie-women for a while and all said the same. In their youth some experienced sex just for curiosity or before they wanted a friend and had to pay for that with sex. But later in life their relationsships were painful because they could hardly tolerate sex any more.
From what I heard it has to do with the overflooding of senses - we hear better, smell more, see more of the details around, remember every remark once made by the other person - all that is present at any moment of an Aspie life. And also when it comes to intimacy and with these sharp overactive senses Aspies can't let themselves go like NTs do at that point. For example, when you smell something strange in the carpet and try to find out what it is, you are distracted - while your partner is not smelling anything and just doing sex, blending out anything else.
As not all Aspies are the same, some may be able to blend out the external input via all senses to a certain extend. But if you can't or won't like to do so, just stay with what feels natural to you. There is no rule, that a human being has to want or like sex at all!