Hi jacig1957
At what point in your cycle was your lining 10mm? It seems quite high for just 1 pump of oestrogel.
I have just had an ultrasound done, which showed my lining to be 11.7mm, which is clearly too high but I am on 4 pumps of oestrogel and just 100 mg of Utro for 14 days per month. I expect I will be having a hysteroscopy to look into this further and discuss other options because I can only tolerate 14 days of vaginal Utro for the same reasons as you and oral use just knocked me out.
My specialist it trialing me on Cyclogest, which, in her experience, is much better tolerated than Utro. However, not all GPs will prescribe it, as it not licenced for use as HRT in the UK yet. It is listed as a progesterone option by the BMS though.