Estrone (E1) is one of the three estrogens, which also includes estradiol (E2) and estriol (E3). Estrone is the least abundant of the three and is relevant to health and disease because it is considered the stronger acting estrogen.

In post-menopausal women, higher levels of E1 when compared to the other estrogens have been implicated in cardiovascular disease, stroke, and certain types of cancer.

If you are taking estrogen replacement therapy, it is important to follow the balance of the three main estrogens in your body. Imbalances in the relationship between E1 and the other two major estrogens are thought to increase the risk for many age-related diseases.

Instructions

Fasting is not required for this test. Take all medications as prescribed. If you are supplementing with any hormones, we suggest taking them approximately 2 hours prior to having your blood drawn to see peak levels. Hormones are best drawn between 8-10 AM. Hormonal contraceptives can interfere with progesterone and estrogen results.

Pre-menopausal women: For a 28 day cycle, blood should be drawn on day 21 (day 1 is the day that bleeding begins). For longer or shorter cycles, count 8 days back from the day your next menstruation would start.

Post-menopausal women: Blood can be drawn any day of the month.