Is the preferred test for male estradiol (E2) measurement as it is far more accurate than the standard estradiol test for men. Estradiol is a form of the female sex hormone estrogen. Estrogen is essential to the health and wellbeing of both men and women although women require higher amounts. Estrogen is essential to our sexual function, mood, reproduction and general health. High and low levels can lead to numerous symptoms and physical conditions. High levels of estradiol (E2) may indicate ovarian, adrenal or testicular tumors. They may be a cause for delayed puberty in boys or early puberty in girls. High levels may also indicate hyperthyroidism and even cirrhosis. Low estradiol levels may indicate ovarian or pituitary dysfunction, turner syndrome and in some cases be due to anorexia. Low levels in men often carry the same symptoms as low testosterone levels.