Many women have difficulties coping with chronic conditions stemming from menopause. These conditions can often be complicated to manage. Symptoms arise from deficiency or dominance of estrogen, progesterone, or testosterone. Hormone replacement therapy involves three main forms of circulating estrogen: estrone (E1), estradiol (E2), estriol (E3). Other important hormones include progesterone (P4), dehydroepiandrosterone (DHEA), and testosterone (T).
Studies have shown that combinations of E1, E2, E3, P4, and DHEA have been effective in treating various vasomotor symptoms that may be associated with menopausal hormone imbalance. Formulations include topical and vaginal creams, oral capsules and orally disintegrating tablets. Various ratios of these hormones exist in the female body, and in order to mimic these ratios, formulations often have to be compounded to contain some proportion of the three estrogens. Triestrogen or TriEst is a common name given to formulations containing E1, E2, and E3 while biestrogen or BiEst is a common name given to formulations containing E2 and E3. BiEst generally contains 80% estriol and 20% estradiol, while TriEst contains 80% estriol, 10% estrone, and 10% estradiol. A prescription written for 2.5 mg of BiEst will actually contain 2 mg of estriol (E3) and 0.5 mg of estradiol (E2) if using a conventional 80:20 ratio.