Lab Tests for Fertility: What Each Hormone Tells You
FSH, LH, estradiol, progesterone and AMH, explained one at a time. What each test measures, when it is taken, and why no single number tells the whole story. Written by Claudia Ferreira.
In this article
If you have been given a page of blood results and left to work out what they mean, this is for you. There are several hormone tests commonly used to assess fertility in women. They help evaluate the hormonal balance and function of the reproductive system.
Here are the most common ones.
1. Follicle-Stimulating Hormone (FSH)
FSH is responsible for stimulating the growth and development of follicles in the ovaries. High levels of FSH can indicate diminished ovarian reserve or a potential problem with ovarian function.
2. Luteinising Hormone (LH)
LH plays a crucial role in triggering ovulation. An LH surge indicates that ovulation is about to occur or has already taken place. LH testing can help determine if a woman is ovulating regularly.
3. Estradiol (E2)
Estradiol is the primary form of oestrogen in women. It is important for follicle development and the thickening of the uterine lining. Measuring estradiol levels can provide insights into ovarian function and the overall hormonal balance.
4. Progesterone
Progesterone levels rise after ovulation and help prepare the uterus for implantation of a fertilised egg. Measuring progesterone levels can confirm if ovulation has occurred and assess the adequacy of the luteal phase.
5. Anti-Müllerian Hormone (AMH)
AMH is a hormone produced by the follicles in the ovaries. It reflects the ovarian reserve and can give an indication of the remaining egg supply. Lower levels of AMH may suggest reduced fertility potential.
Reading them together, not one at a time
It is important to note that the interpretation of hormone test results should be done in consultation with a healthcare provider who specialises in fertility. These tests provide valuable information, but they are just one piece of the fertility assessment puzzle. Other factors, such as medical history and physical examination, should also be considered for a comprehensive evaluation.
The monthly process of preparing for pregnancy involves a complex interplay between the brain, ovaries, and uterus. That sequence sets the stage for ovulation, the release of an egg, the meeting of sperm and egg, and the implantation of a fertilised egg in the uterus. If you want to follow that sequence step by step, it is set out in Ovulation Explained.
Where Body Perfected fits
Testing itself is arranged through your GP or fertility clinic. What happens at the Marylebone clinic is the review: Claudia reads results you already have as part of her intake, alongside your cycle history, symptom picture and any previous treatment.
That review is a standing part of the 12 Weeks Fertility Reset Protocol, and it is why the programme opens with a 90-minute session rather than a quick consultation. Nothing here replaces the advice of the clinician who ordered your tests.
Frequently asked questions
Which blood tests are used to assess fertility?
The most common are FSH, LH, estradiol, progesterone and AMH. Each looks at a different part of the cycle, from follicle development through to whether ovulation has occurred and roughly how much ovarian reserve remains. Your GP or fertility clinic decides which are appropriate for you.
Can Body Perfected order fertility blood tests for me?
Testing is arranged through your GP or fertility clinic. What Claudia does is review results you already have as part of her intake, alongside your cycle history and symptom picture, so the treatment plan reflects the full picture rather than one number.
What does a low AMH result mean?
AMH reflects ovarian reserve and gives an indication of remaining egg supply. A lower result may suggest reduced fertility potential, but it does not predict whether you can conceive, and it should always be interpreted by a clinician who specialises in fertility alongside your other results and history.
When in my cycle should these tests be taken?
Timing matters and differs by test. FSH, LH and estradiol are commonly taken in the early follicular phase, progesterone around seven days after ovulation, and AMH can be taken at any point. Your clinic will tell you the right day for each.