You make a good point, but in all things ASOIAF you can not have an explanation for women using "moon tea" to induce abortions without having a ying yang male counter effect -- although therre are eunichs --some were eunichs for a reason I suspect, like Varys and Theon not because of cruelty but because there were forces behind the scenes influencing events that prevents those two men from reproducing -- that is medieval society in this story and I suspect what's really behind Loras' story is he will be made a eunich also so that with his emasculation/castration he can no longer reproduce and so ends the House Tyrel - he needs to breed his sister Marg (if he still has his bits n pieces while he is locked up before he loses his gonads -- do you see the potential story development? Prison is another form of birth control as old Targ Kings locked their daughters and wives up in towers - maybe the tower of joy wasnt a tower of joy but a way to keep a woman locked up in orer to guarantee she wasn't bred by another man nor that she took steps to abort the baby -- which is what Ashara did (maybe) - Lyanna didn't want to commit suicide after being raped by Rhaegar because I'd suspect it was a "culturally introduced" value somewhere in a reset of time where she did do so at one time - so in a new revised history she keeps the baby - heck, she may have pled to Ned to kill the baby, contrasting what I originally thought that he went ther him self to kill the baby Jon.
However it works out it will be most interesting -- with the introduction of Bran's ability to change and interact with the past anything is possible now -- and you have to wonder who is he competing against in all these mechanisms? Maybe Littlefinger is a hidden Blackfyre I'd suspect an he has powers unbeknown.
the way I se it what has been happening is future "controllers", such as Bloodraven and Bran (who could be the same person) go back into time to introduce revised and tweaked moral rules so that things like getting stabbed in the back doesn't happen -- a we see it ok for Ser Arthur to get stabbed in the back and we also, apparently, know Jamie stabbed Aerys in the back -- which we shall see in a shadow scene of a man stabbing the Mad King- most likely this was done in by a shadow baby born of someone - a Red Priestess obviously. Jamie and everyone present thinks he did it but his mind has been changed also -- in a way so that he and his sister are incestuously breeding-just like Targaryrens (because they are Targs) -- Jamie is a Kingslayer Kinslayerx2 ..
Take the ToJ scene for example, i'd suspect we see another alt scene in the future, and this will be the bomb dropping, in which the events are almost the same but not quite the same -- it will be Bloodraven showing Bran the same location with a different outcome- just slightly tweaked. Backstabbing as a heiness act will be introduced into the knight moral system at some time. Look at the night Watch oath - it was changed in time also to include portions about not fathering children, not marrying -- in response to NW's men fathering children out of wedlock - Craster had a brothel up there I'd suspect, unbeknown to most.