Despite what Joker stupidly says in ME2, Asari obviously have a birth canal. Now we've never seen a pregnant Asari, but nor do we have any reason to think they lay eggs, whatever they do, it likely involves some sort of orifice down there. If a human, or another species of interest, wants to make "use" of that, and I'm sure they do, I don't think the Asari mind, even though it has NOTHING to do with the conception part of their reproduction.