Liz, I agree with all the other comments but would suggest you try using the Utrogestan vaginally. I don't get on with any progesterone and that includes Utrogestan and I take it under sufferance but I have found that taken vaginally it is much, much more effective for several reasons.
Firstly, no breast pain whatsoever which must be a positive - I always had painful breasts when I took it orally. Secondly, it hits the spot and I never get any breakthrough bleeding while I am taking the Utrogestan. Thirdly, no digestive problems which I used to get when taking it orally i.e. indigestion at night and last, but not least, I have heard that when taken orally, only about 25% (this could vary for different women and I doubt it is an exact science) of it reaches the womb whereas taken vaginally, practically all of it does. That was the opinion of one doctor and I stand to be corrected.
Hope that helps.