Yes, exactly. Beyond the character assassination of Teyla--who I do think absolutely and in no uncertain terms would not do that to her friend, that was exactly my problem with it. John had just spent a great deal of time freaking out about Rodney's reaction to it, is written as very gay and as someone to whom sex had not been terribly important in general. And yet he's conveniently suddenly just having sex for reasons he never bothered to very much explain? I could buy Teyla and John maybe having a sudden unexpected moment of mutual attraction that they both had to relucantly say no to. I could even maybe have bought a kiss. But full on sex, no.

If she wanted the sex to be an issue she could have done away with the magic baby machine. If John had had to sleep with Teyla to produce a child for Atlantis it would have made the situation a lot more realistic and complicated. A bit squicky with the implications that Teyla has to be a baby machine herself, but a lot more realistic at the same time.