In premenopausal women the majority of estrogen produced by the body is estradiol (produced primarily in the ovaries), while in postmenopausal women estrone (produced in fat cells) is the type of estrogen present in the greatest amount; however, the body is able to convert one type of estrogen into another to a certain extent. Because of the limited research into potency, delivery methods and conversion of the various estrogens, a valid scientific understanding of compounded estrogen products has not been achieved.  Synthetic estradiol, taken orally, splits when absorbed in the gastrointestinal tract and delivers bioidentical estradiol to the bloodstream. 
More and more physicians are now beginning to research, assimilate and practice natural bio-identical hormone therapy. I believe that within the next 25 years this will be the ideal medical standard for hormone replacement therapy and will be taught to new doctors in our medical schools. Current graduates of medical schools are not being given the current information and updates on this emerging hormone replacement therapy alternative to synthetic treatment. Some doctors are still confusing natural progesterone with synthetic progesterone.
I’ve been taking bioidentical hormones for about a year now. No more hot flashes better energy and libido. I feel like I got my life back. My hair was becoming dry and brittle and outside the hot flashes I had no energy. Always felt tired. Since starting the hormones all of my symptoms have gone away. My doctor shared that the nagging voice in the back of your brain that keeps you from sleeping is a lack of progesterone. Within 24 hrs of started the progesterone capsule I slept through the night like a baby. I am also on estrogens /testosterone cream because both values were low. Feeling great.