Understanding Conventional HRT
The rationale for conventional HRT is that women’s hormone levels decline with age. Replacement, therefore, should reverse troubling menopausal consequences, which include increased risk of heart attack and cancer (Wren 2009; Lenfant 2010; Lee 2010). While the original understanding of menopause and logic behind HRT were theoretically correct, modern science is showing that the true story of HRT is much more complex (Sitruk-Ware 2007).
It is impossible to isolate estrogen and progesterone from other hormones. All steroid hormones are created from cholesterol in a hormonal cascade. The first in the cascade is pregnenolone, which is subsequently converted into other hormones including dehydroepiandrosterone (DHEA), progesterone, testosterone, and various forms of estrogen. These hormones are interrelated, yet each performs unique physiological functions. Biologically sound hormone replacement should focus on a woman's total hormone balance, not only on estrogen and progesterone.
Mainstream physicians are just now beginning to recognize estrogen dominance (Turgeon 2006), a term used to characterize the relative imbalance between excess estrogen and insufficient progesterone. Estrogen dominance helps explain many of the conditions that confront modern women in Western civilization, such as fibrocystic breast disease (Kubista 1990) and cancer (Bentrem 2003; Bradlow 1995; Papaconstantinou 2000). Estrogen dominance can occur in any woman. However, perimenopausal women, who typically experience a more rapid decline in progesterone relative to estrogen, are especially at risk (Fauser 1997).
Conjugated equine estrogen (CEE) is obtained from the urine of pregnant mares (horses) (Bhavnani 2003). CEE is usually given in combination with progestin, a chemical compound modified for the purpose of appearing structurally similar to natural, bioidentical progesterone. However, it is not the same. The structural differences between conjugated equine estrogen and chemical progestin as well as natural hormones are responsible for many of the adverse effects resulting from conventional HRT.
Another major problem with conventional HRT is the estrogen ratio. For example, the ratio in medications such as Premarin® is considerably different than the ratio observed naturally in a woman’s body (Wright 1999).