Hi Jane70
I've been using Utrogestan for 3 1/2 years now - but I've only ever used it vaginally. I've always had a "nil by mouth" approach to HRT as being the most natural way to get hormones into the body and a way to minimise the metabolic breakdown products.
There are side effects undoubtedly - just as some women notice the effects of progesterone during the second half of their menstrual cycle, and indeed in pregnancy.
I use twice the amount that you do - 200 mg daily, V route, but only on a cyclical basis - so maximum 12 days every 5-8 weeks - so I don't have continuous progesterone. I certainly wouldn't want to do this on a conti basis, because of intimacy and also because of not wanting continuous progesterone due to adverse side effects.
The dose I have, the effects build up gradually and seems to vary in different cycles. Sometimes I feel exhausted and leaden for the first few days and then my body acclimatises to it somewhat. Other times I don't feel too bad initially but about day 5 I feel really exhausted and my head gets foggier. Sometimes I get a headache or migraine but not always - and sometimes get this on withdrawal until the progesterone has cleared from my system. It always affects my bladder so that I have to get up to pee in the night once and sometimes twice. I imagine this may happen more with V use than taken orally because a higher concentration will get to the bladder as it diffuses directly while it's down there! I think it affects my breasts too but nothing painful.
You mention about systemic absorption - I have a theory - but I don't think anyone's done any work on it - that less is absorbed systemically if your vaginal tissues are plumped up - much in the same way that Vagifem is not absorbed. It would follow that if you have thin tissues and some degree of vaginal atrophy, more will be absorbed V route than otherwise. Therefore what I do about a week before starting my utrogestan cycle is to do a re-load of Vagifem ( I use vaginal oestrogen as well as sytemic HRT as I need this to keep tissues healthy) for a week and keep it up while using the utro - when I have to do the Vagifem in the mornings - otherwise too much going up there at once
Having said all of that - I still tolerate the side effects of utrogestan because it is a physiological substance - ie it is bio-identical and I know it can't be doing me any untoward harm, that maybe a synthetic progestogen might do.
I would have thought any side effects from oral use would be greater - apart from the bladder effects - but you can only try.
I hope this gives you some idea anyway and hope it's not too long-winded!
Good luck and let us know how you get on .
Hurdity x