Estrone Unit Converter

Estrone (E1) is one of three major forms of estrogen, alongside estradiol (E2) and estriol (E3). It is the weakest of the three, but plays an important role as a reservoir that your body can convert into estradiol when needed.

After menopause, estrone becomes the predominant estrogen in the body because the ovaries greatly reduce production of estradiol. At that point, most estrogen comes from the conversion of adrenal androgens into estrone in fat tissue.

Estrone is present in both men and women, though women typically have higher levels. It is measured as part of hormonal evaluations related to menopause, fertility, and hormone-sensitive cancers.

Estrone is produced by the adrenal glands and adipose (fat) tissue in both men and women. In premenopausal women, the ovaries are also a significant source. After menopause, fat tissue becomes the primary site of estrone production through the conversion of adrenal androgens.