Can HCG Diet Cause Fibroid?

I was told this morning that I have a fibroid and that my enometrial lining is thickening. In two weeks I am going to have a endometrial byopsy. What I was wondering is that I've been on the HCG diet and lost 50 lbs, could the HCG be causing the fibroid? I am 42 years old 5'7' and weight 199. I've never had a problem with fibroids in the past but have had endometriosis. Sorry about the spelling.
Thanks, Lori