.

We're the same age Valerie....!!

And I would say in some respects this whole HRT thang does involve some trial and error....

(Having been on meds an uber-long time now)

I still vary my regime every quarter or so.... as your body is very good to adapting to what you put in it...

As is the case for folks with arthritis.... after a while all NSAID's fail as the body get used to them flushes them out better... and once more you have to change brands to get pain relief...

But back to HRT...

Having taken two big breaks this year.... coming back on did show some improvements for me...

Even though being off them was grim....lol

So keep it safe, but if you notice a drop-off, maybe take a look at brand changes? I don't think there is a general optimum as we're all so uniquely different...

for post surgery, post development women, (serum) levels to maintain bone density is good enough. 100 pg/mL is, imho a good aiming point considering long term estrogen risk.

post menopausal estradiol (serum) ref via merck manual:
at or under 50 pg/mL (at or under 184 pmol/L)

edit: I don't know my levels, haven't had bloodwork since surgery