First, let me state that I have a PhD in microbiology. I am on HRT involving bio-identical hormones (0.5 mg estrace and 100 mg prometrium) that i take continuously. I have one fibroid on the surface of my uterus, which typically was asymptomatic and I assumed was sub-serosal. Recently I had menorrhagia (consisting of heavy and prolonged bleeding). I don't believe I have excessive buildup of the endometrium or a malignancy. Yes, I will see my gynecologist for an intra-vaginal ultrasound. Due to controversial information in the literature on effects of progesterone on fibroids, should I consider taking 200 mg prometrium or synthetic progestin in the future to attempt to limit growth of the fibroid and/or limit the thickness of the endometrium?