Hi Schroomer I hope you turn out to be a fraud (IUSWIM) it always the best outcome to find out you dont have AS Lots of hand holding on offer till then!
There is a doc on the AS site called HSG vs sHG that you might find useful. Its something I had to look closely at myself. The crux of the matter is this:
hysteroscopy is the only way to "see" scar tissue, so once the camera is in there you get a 100% accurate picture. However diagnositic hyst is a bit of a waste of theatre time and there is a risk of developing IC in later pregnancies if you repeatedly dilate the cervix, so most A list doctors want to do an operative hyst only and do the diagnosis part via sHG/HSG.
It means you end up in the unenviable position of knowing you have AS but not exactly how bad until AFTER you wake up from the GA and its all been taken care of.
sHG (saline solution squirted in uterus and 4D ultrasound scan pics taken) This is IMO "easier" (less painful/uncomfortable) and is done in the doctors office, not hospital. Its also better for detecting scar tissue (but this does very much depend on who is looking at the images) always ask for them to be recorded on CD so you can show it to an expert afterwards.
HSG (contrast dye which sticks to scar tissue is squirted in uterus and x ray pics taken) This has the advantage of showing if your fallopian tubes are open as well as the state of your uterine cavity. Its done in hospital by a radiographer and gynecologist. (again ask for the CD)
Dr Lower also diagnoses via 4D ultrasound alone, he is the only doctor that does this, but as you can see from missedhappinesss post, it isnt always accurate.
If you have scar tissue blocking your cervix (as I did) then blood cant get out and liquid cant get in, so the sHG or HSG will "fail" and this itself will give you your AS diagnosis (though sometimes it is just called cervical stenosis (blocked cervix)
Doctors in the USA routinely do both sHG and HSG and then the operative hyst.
In conclusion, because you are having no periods at all, there is a chance that your cervix is blocked with scar tissue, in which case I wouldnt do a hysteroscopy because the doctor may just try to force their way through and make things worse. I would try a sonohysterogram (sHG) because its the least stressful/invasive/expensive and if the doc has trouble "getting in" then you need go no further. If it does work, then you could move straight to the operative hysteroscopy where they can do an HSG at the same time to check the state of your tubes.
I said early push for the HSG because I gather from reading on these boards that that is what the NHS usually offers first - but its well worth asking for the sHG. Maybe they do this all the time and I dont know about it? If you were thinking about going private sHG would be a lot cheaper.
Right, I think I have written too much now, hope I havent confused you!