I, too, have this same experience. Full hysterectomy at 42, was on Estradiol for 15-18 years. My hot flashes were minimal in comparison to what some women go through. When I stopped the Estradiol I started having them but, not right away. I am now 64 and still get them, I attribute them to be associated with the hysterectomy and stopping the Estradiol but, I have never talked to my dr. about it.