Many women at some time have a blood test for oestrogen. It might be during pregnancy (or if a woman is having difficulty getting pregnant); if their menstrual cycle is unusual; if the woman is showing the signs of menopause; or for some other reason.
What is being tested?
Oestrogen is a sex hormone produced both by women and men, although in much greater amounts in women.
Oestrogen helps female sex organs — the ovaries, fallopian tubes, uterus and the vagina — to grow and mature. It also helps create other female characteristics, such as the breasts.
Oestrogen levels rise naturally during puberty and fall after menopause.
Your doctor might look for 3 types of oestrogen in your blood:
- oestradiol — important for ovulation, conception, pregnancy, healthy bones and cholesterol levels in women
- oestriol — important during pregnancy; oestriol levels usually start to rise after the eighth week of pregnancy
- oestrone — the most important oestrogen after menopause
Why would I need this test?
Your doctor might suggest a blood test for oestrogen if:
- your menstrual cycle is abnormal, or you have heavy bleeding
- you can't get pregnant
- you have symptoms of menopause
- you have symptoms that might mean your hormones are unbalanced
If you are pregnant, you might have a blood test for oestrogen:
- as part of screening for Down syndrome in your unborn child
- to check that your placenta is working properly
Young girls occasionally have blood tests for oestrogen if they are developing sex organs when very young. Young boys occasionally have blood tests for oestrogen if they are developing breasts.
How would you prepare for this test?
You don't have to do anything special before a blood test for oestrogen.
Understanding your results
The levels of each type of oestrogen in your blood can be different from day to day. The can also vary throughout your pregnancy. They can change as you get older too.
So, a one-off test is only a guide. You might need several tests over weeks or months to check what is really happening with your oestrogen levels.
A result outside the normal range might not mean you have a health problem, or that you need to be worried. Your doctor is the best person to talk to about your blood test results.
Read healthdirect's Guide to blood testing for more general information.Lab Tests Online has more information on blood tests in general and on tests for oestrogen in particular. The healthdirect Question Builder can help you prepare for a doctor's appointment.
The Virtual Medical Centre also has more information on oestrogen and puberty.
Last reviewed: May 2018