Anglichanka, I'm not surprised you are having problems with that high dose of Utrogestan. In my opinion, that is far too much to be taking with a 50mcg patch (full stop actually) and you should definitely be using it vaginally for two reasons. Firstly, you can get away with using less that way because most of it reaches the womb and therefore works better at clearance/thinning and secondly, it has fewer side effects when used vaginally. You can lose up to 50% in your digestive system when you take it orally.
I don't like Utrogestan at all but it is the lesser of several evils for me. I can just about stomach it if I take 100mg vaginally for 7 days every 5 weeks - I don't have a choice, it's either that or a hysterectomy.
If I were you, I would halve that dose to 100mg, use it vaginally (although you will actually be getting about the same dose by using it vaginally instead of orally) and cut back to 10 days. Depending on how you feel, you could cut back further to 100mg for 7 days each month but I would recommend you have regular scans to make sure you are getting proper clearance.