Serum free estriol measurement is used, inter alia, as part of the "alpha test or triple test" to assess the risk of a pregnant woman carrying a fetus with genetic abnormalities such as Down syndrome, to assess the risk of preterm birth, prenatal diagnosis of steroid metabolism abnormalities in the developing fetus and evaluation of estrogenic and estrogenic drug metabolism.
Estrogens are found in the body in various forms, and include estradiol, estriol and estrone. As estrogens are produced by the adrenal cortex, ovaries and testes, the determination of estrogen levels can be used in the evaluation of all three glands.
Estradiol (E2, 17-β-estradiol) is the most active of the forms of estrogen in stimulating endometrial growth. It also suppresses the production of follicle stimulating hormone (FSH) and stimulates the production of luteinizing hormone (LH). Estradiol is produced by conversion of testosterone. Estradiol levels are used to evaluate ovarian function and to diagnose the causes of early puberty in girls and gynecomastia in men. It is often used to determine if amenorrhea is the result of menopause, pregnancy, or some other medical problem. In patients with infertility problems, estradiol measurements are taken prior to IVF. Estradiol measurement can also be used to monitor the effectiveness of hormone replacement therapy.
Estriol (E3) is usually measured during pregnancy to evaluate placental function and fetal health. Estriol, together with α-fetoprotein (AFP) and chorionic gonadotropin (HCG), are measured together as an "alpha test or triple test" to assess the risk of a pregnant woman carrying a fetus with genetic abnormalities, such as Down syndrome.
Estrone (E1) is derived from the conversion of androstenedione to the adrenal cortex. Its function is not clearly understood, but elevated estrone levels without concomitantly high progesterone levels have been associated with an increased risk of endometrial cancer. Estrone levels can be used to help diagnose ovarian cancer, Turner's syndrome, hypophyphism, gynecomastia (in men) and menopause.
Possible Interpretations of Pathological Values
- Increase: Adrenal hyperplasia, adrenal tumors, cirrhosis, estrogen-secreting ovarian tumors, liver failure, Klinefelter syndrome, normal pregnancy, early adolescence, renal failure, tumor
- Decrease: Amenorrhea, neurogenic anorexia, vigorous exercise, hypogonadism, hypophysis, menopause, ovarian failure, Stein-Leventhal syndrome, Turner syndrome
- Medications that may increase estrogen levels: Ampicillin, diethylstilbestrol, estrogen, hydrochlorothiazide, meprobamate, oral contraceptives, phenazopyridine, prochlorperazine, tetracycline
- Medications that may decrease estrogen levels: Clomiphene, dexamethasone, estrogen inhibitors
Laboratory test results are the most important parameter for the diagnosis and monitoring of all pathological conditions. 70%-80% of diagnostic decisions are based on laboratory tests. Correct interpretation of laboratory results allows a doctor to distinguish "healthy" from "diseased".
Laboratory test results should not be interpreted from the numerical result of a single analysis. Test results should be interpreted in relation to each individual case and family history, clinical findings and the results of other laboratory tests and information. Your personal physician should explain the importance of your test results.
At Diagnostiki Athinon we answer any questions you may have about the test you perform in our laboratory and we contact your doctor to get the best possible medical care.