Hi Happyhooker. How long have you been taking HRT and what was your cycle doing before you started it? Were your periods still fairly regular or had you started skipping them?
If you've been taking HRT for a while then yes the recommendation is to try to change to continuous combined HRT when you reach the age of 54 but if you then still get breakthrough bleeding which persists after 6 months then usually the recommendation would be to go back to cyclical, or possibly increase the progestogen if this is possible and is tolerated.
I am still on sequential HRT in mid 60's having started when I was just under 54, because I don't like the progesterone. It does sound like your own cycle could be coming into play but the other reason is that actually 100 mg utrogestan especially taken orally is just not sufficient to keep the womb lining thin when you are on a high dose of oestrogel. 4 pumps is a high dose if you are absorbing it well.
That being the case I would contact the doctor because ideally you should really have a scan just to check that the lining is not overthickened, if the bleeding is significant. If it's your cycle then that's fine. Cyclical hRT will sort it out so you know when it's coming. If it's too little progesterone compared to oestrogen (and your womb lining has thickened as a result) then ideally after undergoing treatment to shed the lining, you should take a higher dose of progesterone if you still want to be on continuous combined HRT.
Hopefully you can have a phone consultation with your doctor and perhaps move to cyclical HRT in the first instance with their permission, even while ( maybe?) awaiting a scan, if this is suggested?
Does that make sense?
Hurdity x