Key takeaways
- Follicle stimulating hormone (FSH) is the pituitary signal that drives egg development each cycle, and the result is usually most informative when taken on cycle days 2 to 5.
- FSH varies from month to month, so a single reading is a snapshot, not a fixed number.
- Over 45, menopause is usually diagnosed from symptoms and period pattern without an FSH test; under 45, FSH may be used as part of a doctor's assessment.
- A standalone FSH test at Blood London costs £71.25 plus the £50 blood draw, with results back in 1 day.
- For a fuller fertility or hormone picture, the Female Hormone Blood Test adds LH, oestradiol and testosterone, and the Fertility Blood Test adds anti-Müllerian hormone (AMH).
- Your laboratory report shows the reference range next to your result; a doctor reads FSH alongside your age, cycle pattern and symptoms rather than as a number on its own.
FSH is a hormone made by the pituitary gland that signals the ovaries to develop an egg each cycle, and it is used to help assess fertility and, alongside other markers, the approach to menopause. Book an FSH blood test to check your level, ideally on the cycle day your clinician has advised.
Book an FSH blood test at 117a Harley Street: £71.25 plus the £50 blood draw, results in 1 day.
When in my cycle should I take an FSH test?
FSH is usually most useful when tested on cycle days 2 to 5, because this is when it best reflects your ovarian reserve and cycle pattern. Outside that window, the same test can still be taken, but the result is harder to interpret against typical reference patterns. Count day 1 as the first day of full bleeding. If your periods are irregular or have stopped, ask a doctor when to test.
Why does my FSH level change from month to month?
FSH naturally varies from one cycle to the next, and even within a single cycle, because it responds to changing hormone signals between the pituitary gland and the ovaries. This is why a single FSH result is read as one data point rather than a fixed measurement of your fertility or hormonal status, and why a clinician may suggest repeating it or reading it alongside other hormones.
Can FSH tell me if I'm in menopause?
Not on its own. If you are over 45 and have typical symptoms, NICE advises that perimenopause and menopause are diagnosed from your symptoms and period pattern, without an FSH test, because levels fluctuate during perimenopause and a single result does not give a clear yes or no answer. If you are aged 40 to 45, a doctor may use an FSH test as part of the assessment, and under 40, repeated FSH tests are used to check for premature ovarian insufficiency. FSH is not a reliable guide if you are using combined hormonal contraception or HRT.
| Test | What it includes | Price | Turnaround |
|---|---|---|---|
| FSH (standalone) | FSH only | £71.25 plus £50 blood draw | 1 day |
| Female Hormone Blood Test | FSH, LH, prolactin, oestradiol, testosterone, SHBG | £245 plus £50 blood draw | 1 working day |
| Fertility Blood Test | FSH, LH, prolactin, oestradiol, AMH, Free T4, TSH | £395 plus £50 blood draw | 1 working day |
| AMH (standalone) | Anti-Müllerian hormone only | £150 plus £50 blood draw | 1 day |
A single FSH test gives one part of the picture. The Female Hormone Blood Test adds LH, prolactin, oestradiol and testosterone for a broader hormone map. The Fertility Blood Test adds anti-Müllerian hormone (AMH), which reflects ovarian reserve and, unlike FSH, can be taken at any point in your cycle. You can also book AMH on its own.
What does a high FSH result usually mean?
A higher FSH result can reflect reduced ovarian reserve, and is one of the patterns sometimes seen as women approach menopause. It is not a diagnosis by itself, and your doctor will weigh it against your age, cycle pattern, symptoms and any other hormone results before drawing a conclusion. If you are under 40 and your periods have become irregular or stopped, see a doctor, as this needs assessment whatever a single FSH result shows.
What does a low FSH result usually mean?
A lower FSH result can be seen in some causes of irregular or absent periods, including patterns linked to the pituitary gland or hypothalamus rather than the ovaries themselves. As with a high result, this needs to be read alongside your wider clinical picture rather than in isolation.
Do I need to fast before an FSH test?
No, fasting is not needed for an FSH test. Timing within your cycle matters more than food, so mention your last period date when you book or attend.
How FSH testing works at our Harley Street clinic
Like all our private blood tests in London, you can walk in or book an FSH test online at 117a Harley Street, seven days a week, with no GP referral needed. The standalone test costs £71.25 plus the £50 blood draw, and results are usually back within 1 day by email. You can add a doctor review of your report to your test for £75. If you would like your result discussed alongside your symptoms and history, a specialist gynaecology consultation at Gynae Clinic can put the number in context.
Book your FSH blood test or Fertility Blood Test online, or walk in seven days a week at 117a Harley Street. Start your booking.
Frequently asked questions
Is a high FSH always a sign of menopause?
Not on its own. A raised FSH is one pattern sometimes seen as women approach menopause, but it fluctuates and is read alongside your age, symptoms and period pattern rather than as a stand-alone diagnosis.
Does taking the contraceptive pill affect my FSH result?
Yes. Combined hormonal contraception and some progestogen-only methods suppress FSH, so a result taken while you use them is not a reliable guide to fertility or menopause.
How is FSH different from AMH?
FSH is a pituitary hormone that varies with your cycle day and month to month, while AMH reflects ovarian reserve more steadily and can be tested at any point in your cycle. They are often looked at together for a fuller fertility picture.
Can I test FSH if I'm not trying to conceive?
Yes. FSH is also used to help investigate irregular periods, amenorrhoea and perimenopausal symptoms, not only fertility questions.
How quickly will I get my FSH result?
Results for the standalone FSH test are usually available within 1 day by email.
References
- NHS: Menopause
- NICE guideline NG23: Menopause, diagnosis and management
- NHS: Early menopause
- NHS: Infertility
- Lab Tests Online UK: FSH test