Well, I have put it off for months. Finally called my OBGYN about this. They made me come in for a consultation only to be told she doesn't do those kinds of tests, I have to see a doctor who works with those specialty tests. I do have a name of an OBGYN that does this. I called and yippee. I have an appointment. Not until Mid May. They told me Doctor only does blood work - a hormone panel. So why can't my OBGYN do that? I have tried premerin (sp?), topical gel, HRT patch, all starting low dose moving on up with no releif at all. I too had the overnight menopause. Only NOBODY bothered to tell me that a hysterectomy was going to do that to me. I obviously didn't do my homework at all! those that use bioidentical how is it? does it take a while or is it right away? Hot flashes, omg I can time them. Every 8 minutes. flipping off blankets, taken off clothes, then turning on the portable heater cause I am freezing. Over and over and over again. I just can't take it. Nothing else worked. I am giving this a shot.