The amazing thing about all this, which I'd not known before, is that xy chromosome people, with complete androgen insensitivity, will develop just as a woman would, breasts, hips and all (probably not menstruation, though, I imagine).
If they're androgen insensitive, they don't gain any of the advantages of high testosterone. And they are a woman in all bar chromosomes and reproductive organs.
But she hasn't developed breasts or hips and has a pretty perfect male body? her vagina is connected to nothing that a females vagina is normally connected to in terms of reproduction because female internal organs simply aren't there, she has internal testes which is the primary male reproductive sexual organ and lets face it looking at the photo dowie posted how many men on here wouldn't want to have that same physique? I'm not sure how you can argue androgen insensitivity when she has such an impressive male physique.
They wouldn't know they weren't a woman until they tried to conceive, or had certain tests.
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She's been brought up a woman, quite reasonably believed she was a woman.
You would know at around puberty, it's understandable that before then that her parents would think she was a girl because externally she had a vagina but internally her sexual reproductive organs seem to be all male and her body has developed as a male body would, not female. Scientifically she has XY male chromosomes.
This isn't the 'stolen valour' of a lifetime male transitioning to female and expecting to co-opt resources or allowances or platforms hard fought for by women (see Trans Exclusionary Feminism). She's been brought up a woman, quite reasonably believed she was a woman.
It's very little like trans issues.
Well not all trans people are transitioning to win scholarships and medals either but it's still unfair for them to compete against women, Semanya was born with a mostly male body (inwardly and biologically), she has a vagina instead of a penis due to a birth defect, her puberty appears to have been far more towards the male end of the spectrum which is understandable since she had internal testes and high testosterone levels. At the end of the day you have someone who (knowingly or not) has spent the better part of their life developing a male body and is now competing against women in physical competition.