Oprah Whinfrey is currently doing research on hormone replacement therapy and you can find indepth information on the subject on her website by using the following link: Oprah Gets Passionate About Hormone Replacement Therapy Below are some great science based, peer reviewed articles: Study- Epigenetics in Clinical Practice Bio-Identical Hormone Replacement Therapy The WHI Study and How It Relates to BHRT A Comparison Between Oral and Transdermal HRT The Difference Between Progesterone and Progestins The Beneficial Effects of Estriol Sedative Effects of Progesterone Greater Patient Satisfaction with BHRT Progesterone vs. Synthetic Progestins The Role of Compounding and Customizing Estrogen in HRT Synthetic Progestin Shown to Have Greater Risk of Breast Cancer versus Bio-Identical Progesterone Flawed Testosterone Analysis Spurs Misleading Media Headlines by LifeExtension The Bioidentical Hormone Debate Estriol - The Good Estrogen