"What I mean is, if now in peri it's when our periods begin to be a bit unpredictable and aren't always around the same duration like they used to be, this makes it difficult to try and time progesterone correctly, doesn't it."
rferdi, at that point you would probably be best switching to continuous but taking a 3-5 day break to allow a bleed. That enables anything that has built up to shed on schedule so no doctors get worried about unscheduled or unpredictable bleeding.
If a period comes slightly early one month, that's fine. I mean, 2 days less of utrogestan isn't going to be harmful. And if that begins to happen every month, with a shorter cycle, you just move forwards when you start it.
As I said... it's the people who keep taking it continuously who end up with erratic bleeding. When their own body wants to shed (have a proper period) probably due to a drop in estrogen from ovaries, it can't shed properly because we're giving it the opposite message with the utrogestan. So it doesn't fully shed and then you get breakthrough bleeding and spotting at other times of the month - and then you don't know where you are...