I have never taken it orally Jules - I have had trouble in the past with tablets, nausea and reflux and I definitely have problems with progesterone generally so having read everything here - I was never going to risk it. Oral hrt has to go through the stomach and get processed by the liver. That process can cause different side affects plus being digested by stomach acid is known to change how efficiently the body processes and absorbes the hrt.
I also don't take it continuously either because I suffer from hormonal depression and when I took another form of progesterone called Provera it made me manic and suicidal big time! I use the utrogestan on a cycle vaginally although I am post menopausal at 57 and it is manageable and by the far part of the best system of hrt I have had for me and I have had to go through quite a few (my hrt journey started 10 years ago) to find the right one but I use oestrogel 4 pumps and utrogestan on a cycle and have done for 7 months.
For the first time in years I am actually getting a life!
It is very much trial and error and you need bucket loads of patience unfortunately