How is it used?
Oestradiol levels are used to evaluate ovarian function and to help diagnose the cause of precocious puberty in girls (very early signs of puberty) and gynaecomastia in men. Its main use has been to help diagnose the reason for (for example, to determine whether the cause is menopause, pregnancy, or a medical problem). In treatment of sub-fertility, repeated measurements are used to follow follicle development in the ovary in the days prior to in-vitro fertilisation. Oestradiol may also be used to monitor menopausal hormone replacement therapy, if given as oestradiol by implant.
Oestriol, along with alpha-fetoprotein (AFP maternal) and human chorionic gonadotropin (hCG), is used to assess the risk of carrying a fetus with certain abnormalities, such as Down syndrome.
Oestrone is rarely measured to aid in the diagnosis of an ovarian tumour, Turner’s syndrome, and hypopituitarism. In males, it may help in the diagnosis of gynaecomastia or in the detection of oestrogen-producing .
When is it requested?
Your doctor may request oestradiol (along with other tests) if you have symptoms such as pelvic heaviness, abnormal vaginal bleeding, abnormal menstrual cycles, or if you are having hot flushes, night sweats, difficulty sleeping or symptoms of the menopause. If you are on hormone replacement therapy, your doctor may use oestradiol levels to monitor your treatment, but only if oestrogen is given in a form that can be measured by the laboratory.
If you are having difficulty conceiving and becoming pregnant your doctor may use oestradiol measurements over the course of your menstrual cycle to monitor follicle development prior to in vitro fertilisation techniques (timed with a surge in your oestradiol level).
If you are pregnant, unconjugated oestriol (oestriol not bound to sex hormone binding globulin) may be measured in the 15th to 20th week of gestation as part of the triple screen.
What does the test result mean?
Increased or decreased levels of oestrogen are seen in many metabolic conditions. Care must be used in the interpretation of oestrone, oestradiol and oestriol levels because their levels will vary on a day-to-day basis and throughout the menstrual cycle. If your doctor is monitoring your levels, s/he will often be looking at trends in your levels, rising or falling over time, rather than at single values. It must be remembered that a diagnosis cannot be made solely based on one test result.
Is there anything else I should know?
Beyond daily and cycle variations, illnesses such as hypertension (high blood pressure), anaemia, and impaired liver and kidney function can affect oestrogen levels in the body.