Thanks all.
Hurdity - this is interesting information, particularly given that the Conti patches appear to have alleviated around 80% of my wife's symptoms - I am convinced that she just needs slightly more estrogen - and she doesn't seem to have the standard "progesterone intolerance" symptoms (although who knows whether some symptoms remain cos of insufficient estrogen or a reaction to the constant progesterone) - we're just reluctant to change the regime entirely. She has had 2 hours of breakthrough bleeding and nothing else in the 3 months since she started it. I guess we should ask the GP for the go ahead before we slap on an extra half a patch though.............should she qualify for "routine" scans on her womb lining since she's on HRT, or do they only scan when there's a cause for concern - i.e. heavy/unexpected bleeding etc? Thank you!