Hi
sorry to hear about your situation and being diagnosed so young with meno.
What type of pill were you on for 20 years? Just so we're clear on that part.
In terms of "osteopenia" its showing a lower density not full osteoporosis.
So that is good in a way.
In terms of the pill or HRT, there still needs to be good diet to help keep calcium levels high.
Also calcium is pretty much useless in high amounts without other things including vitamin D to help build healthy bones.
Considering they've told us all since I was young to keep out of the sun or put on high factor sun cream then that does not help either.
If your looking at HRT tablets estradiol 2mg medium options or above are used to treat osteoporosis. I think there is a similar level in the patches estradiol 50mcg but ask the doc to check on that. Anything less then there is a risk it won't help as much.
http://www.menopausematters.co.uk/postmeno.phpTake the list along with you to your doctor. Explain what you understand and see what they say.
It might be good to get the doc to refer you to a dietitian to review how you can improve your diet to help too.
All the best on your long journey.