it's a competitive reproductive instinct.  in many species of animals the females, and sometimes the males, will go around and kill off the offspring of other competing animals of the same species. for example, some storks will tip over the nests of other birds in their area (ironic that the stork is a symbol of fertility). this ensures a better chance of their own ability to reproduce. also, their own offspring have access to more resources (i.e. less competition). now, a woman can't just go a round and kill a bunch of other women's children. that's highly antisocial and would be very counterproductive. so what's the next best thing? yep, abortion. by promoting abortion, all these women are really doing is encouraging a practice that eliminates their competition. it's highly passive aggressive, and i would argue these women aren't really aware of what they're doing at a conscious level. it's more of a reflexive instinct they have when under reproductive pressure. that's why the most rabid pro abortion women are > close to the end of reproductive years > fat > ugly > don't have much money these women instinctively know they will likely lose the game of reproduction and so they promote abortion to eliminate their competition and hopefully give themselves a better shot.   yeah, this is not far off
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