Tri-estrogen is, not so surprisingly, a combination of the three major estrogens your body makes -- estrone, estradiol, and estriol. Usually it is produced in as 10% estrone; 10% estradiol, and 80% estriol, but this ratio can be adjusted depending upon your specific needs.  Tri-est can come in different forms, including oral (capsules) or transdermal (gel or cream).

The theory behind tri-estrogen is a simple one: By taking it, you get the benefits from three different estrogens, and they are in a ratio similar to that which your body produces. The bulk of tri-est is estriol, which is the weakest form of estrogen produced on our bodies -- and, as mentioned before, not only is it the least likely to cause breast cancer, some studies have shown that it actually helps prevent it. So by taking all three estrogens -- very small doses of the stronger ones and a higher one of the weakest one, you can eliminate menopausal symptoms, fight osteoporosis and heart disease and help prevent the increased risk of breast cancer.

It’s a great theory, and one that bears watching. The only problem: As with other newer forms of estrogen, there haven’t been any long-term studies done on this.

• Standard dosage: 1.25 mgs twice a day to treat mild to moderate symptoms ; 2.5 mgs twice a day for moderate to severe estrogen deficiency; also available in 5 mg dosage
• Pros: Natural; appears to have fewer health risks than other estrogens, while preventing osteoporosis and heart disease and eliminating symptoms.
• Cons: May be too weak for some women, particularly those who have just had surgical menopause; no long term studies have yet been conducted on this form of estrogen replacement