I never realized how good I was a pooping until I no longer was.

Six months after starting HRT, I started having more difficulty going to the bathroom. I read some archived older posts here about spironolactone as a possible culprit, but I have, at various intervals gone off Spironolactone for a couple of weeks or so, and not noticed any improvement.
I'm pretty sure it is estrogen that constipates me. It is (barely) manageable with fiber supplementation (and lots of water, of course), but I still go through spells of cramps, decreased appetite, bloating and bleeding. Endoscopy shows only hemorrhoids, which is what one would expect with chronic constipation.
How common is this? My endocrinologist doesn't seem to thing that it's a thing.