Re the freezing of utrogestan - a few years ago (2011!) on here another member did that for the same reason - but not sure of the outcome. I had a search but can't find reference to it so I think we must have discussed this by e-mail as we were in touch back then.
In terms of temperature inactivation - the product info does not list any special storage conditions for utrogestan re temperature so it may well be OK in this regard. However more to the point would be that if taking vaginally this is not advisable because you would not want it to be frozen when you inserted it
, so the progesterone from the cut end would leak out too quickly and therefore even less would probably get to your uterus. The capsule is designed to at least be slightly slow release ie overnight rather than all at once so I don't think your uterus would be protected so well - especially as you would be using much less than the licensed dose. If using orally then I doubt this would be sufficient (50 mg) - but depends on your oestrgoen dose.
Can you explore these different options with your specialist? For example given your circumstances could you be put on a shorter cycle under supervision with regular scans? Can you get a referral to Bournemouth (the nearest NHS menopause clinic to the West Country!) - although I think there is a long wait?
Unfortunately the amount of progesterone needed to protect the uterus is higher than some women can tolerate taken vaginally or orally. Orally especially, because so much is lost - you need to take a higher amount. The initial feeling of calm is probably because it has a sedative effect and in small doses some women find this helpful but in larger doses or as it builds up the sedation can become fatigue, lethargy, bloating, headache etc - not nice.
I am so sorry to hear of your ongoing problems and do hope you manage to find a regime that works for you so that at least you feel better more of the time than not.
Hurdity x