ESTRADIOL BLOOD TEST MEASURES THE LEVEL OF A HORMONE CALLED “ESTRADIOL” IN THE BLOOD STREAM. ESTRADIOL IS A SEX HORMONE AND  IS ONE OF THE THREE HORMONES ESTROGEN (ESTRONE, ESTRIOL) PRODUCE BY THE HUMAN BODY. IN FEMALES ESTRADIOL BLOOD TEST SHOWS HOW WELL YOUR “OVARIES, PLACENTA, OR ADRENAL GLAND WORKS” OR IF YOU HAVE SIGNS OF AN OVARIAN TUMOR, AND TO MONITOR PATIENTS WITH “HYPOPITUITARISM AND WOMEN UNDER GOING CERTAIN FERTILITY TREATMENTS.  ESTRADIOL PLAYS AN IMPORTANT ROLE IN SEXUAL DEVELOPMENT