Your Complete Guide to Fertility Testing: What Each Test Measures and Why

There is a particular kind of vulnerability that comes with fertility testing. You are handing over samples, submitting to scans, and waiting for numbers that feel like they will define your future. Every result carries weight. Every appointment brings the possibility of answers you are not sure you want to hear.

The uncertainty can be overwhelming. You might find yourself Googling test names at midnight, trying to decode what AMH means or whether your FSH is "good." You might dread the results, or desperately want them, or both at the same time. These feelings are completely normal.

Understanding what each test actually measures, and what it can and cannot tell you, helps take some of the mystery out of the process. Knowledge does not eliminate anxiety, but it can make you feel less like a passive participant and more like someone who understands what is happening to their body. This guide walks through the standard fertility tests, what the numbers mean, and how doctors use them to build a picture of your fertility.

Because you deserve to understand the process, not just endure it.

Why Testing Matters

Fertility testing serves several purposes. It helps identify potential causes of difficulty conceiving. It guides treatment decisions. And sometimes, it provides reassurance that everything is working as it should.

Testing is typically recommended when:

• You have been trying to conceive for 12 months (if under 35) or 6 months (if 35 or older), or straight away if you are over 40
• You have irregular periods or other symptoms suggesting a potential issue
• You have a known condition that might affect fertility
• You want a baseline understanding of your fertility status

If you are unsure whether testing is right for you, our guide on when to see a specialist can help you decide.

The goal is not to find something wrong. The goal is to gather information that helps you and your doctor make informed decisions. As part of your fertility education journey, understanding what these tests measure empowers you to participate fully in your care.

Tests for Women

Female fertility testing typically evaluates three main areas: ovarian reserve (how many eggs you have), ovulation (whether you are releasing eggs), and reproductive anatomy (whether the physical structures are functioning properly).

Ovarian Reserve Testing

Ovarian reserve refers to the quantity of eggs remaining in your ovaries. These tests do not measure egg quality directly, but quantity often correlates with options and treatment approaches.

AMH (Anti-Mullerian Hormone)

What it measures: AMH is a hormone produced by cells in your ovarian follicles. The level reflects how many follicles (and therefore eggs) you have.

How it is done: A simple blood test, which can be taken at any point in your menstrual cycle.

What the numbers mean: There is no single agreed set of cut-offs, and AMH falls naturally with age, so your result should always be read against your age and your lab's own reference range (some labs report in pmol/L rather than ng/mL). As a rough guide, based on figures in ASRM's guidance:

Important context: AMH tells you about quantity, not quality. A woman with low AMH might still have good quality eggs. AMH is one piece of information, not a verdict.

What it cannot tell you: Whether you will get pregnant naturally (studies show women with low AMH conceive at similar rates to women with normal levels, and NICE advises against using AMH for this), how long you have to conceive, or the quality of your remaining eggs. Its main use is predicting how you are likely to respond to IVF or egg freezing medication.

FSH (Follicle-Stimulating Hormone)

What it measures: FSH is released by your brain to stimulate your ovaries to develop follicles. When ovarian reserve is low, your brain produces more FSH to try to compensate.

How it is done: Blood test on day 2-4 of your menstrual cycle (day 1 is the first day of your period).

What the numbers mean: An early-cycle FSH above about 10 IU/L is generally considered raised and suggests lower ovarian reserve. Exact cut-offs vary between labs and assays.

Important context: FSH can vary significantly from cycle to cycle, and many women with low reserve still have a normal FSH, so a normal result doesn't rule it out. A raised result is fairly specific but should be interpreted alongside AMH and ultrasound. NICE now advises against using FSH to predict how you will respond to IVF or how successful it will be.

Antral Follicle Count (AFC)

What it measures: The number of small follicles visible on your ovaries at the start of a menstrual cycle. Each antral follicle contains an immature egg.

How it is done: Transvaginal ultrasound on day 2-5 of your cycle.

What the numbers mean: Like AMH, there is no single agreed cut-off, and counts fall with age. A low count suggests fewer eggs are likely to be collected with stimulation. A very high count (ASRM uses more than 24) signals a higher risk of over-responding and of ovarian hyperstimulation syndrome (OHSS). Many small follicles can also be a feature of PCOS (now also called PMOS), which is diagnosed using specific criteria rather than AFC alone.

Important context: AFC gives a visual confirmation of reserve. In an experienced clinic it is about as good as AMH at predicting how you might respond to fertility medications, but like AMH it doesn't predict natural conception.

Hormone Testing

Beyond reserve markers, several hormones affect fertility and are routinely checked.

Estradiol (E2)

What it measures: A form of estrogen produced by developing follicles.

When tested: Day 2-4 of your cycle, usually alongside FSH.

Why it matters: High estradiol early in the cycle can suppress FSH artificially, making FSH appear normal when it might not be. The two tests together give a clearer picture.

LH (Luteinizing Hormone)

What it measures: LH triggers ovulation. It is also checked as a ratio with FSH.

Why it matters: LH is measured alongside FSH if your cycles are irregular. Some reports include an LH-to-FSH ratio, but this is not part of the internationally recommended criteria for diagnosing PCOS. Tracking LH in urine also helps predict when ovulation will occur.

Prolactin

What it measures: A hormone normally involved in milk production, but elevated levels can interfere with ovulation.

Why it matters: High prolactin (hyperprolactinemia) is a treatable cause of irregular periods and infertility. NICE recommends testing it if you have an ovulation problem, breast milk discharge or a suspected pituitary problem, rather than for everyone.

Thyroid Hormones (TSH, T3, T4)

What it measures: Thyroid function affects nearly every system in the body, including reproduction.

Why it matters: Both overactive and underactive thyroid can disrupt ovulation and increase miscarriage risk. Thyroid issues are common and treatable. NICE recommends thyroid tests for women with symptoms of thyroid disease, although many fertility clinics check thyroid function routinely.

Progesterone

What it measures: Progesterone rises after ovulation to prepare the uterine lining for implantation.

When tested: About 7 days after expected ovulation (around day 21 in a 28-day cycle).

Why it matters: Low progesterone at this point suggests you may not have ovulated. This test confirms whether ovulation is occurring.

Anatomical Tests

Even with good eggs and proper ovulation, structural issues can prevent pregnancy.

HSG (Hysterosalpingogram)

What it is: An X-ray procedure where dye is injected through the cervix to visualise the uterus and fallopian tubes.

What it shows: Whether your tubes are open (patent) or blocked, and whether your uterine cavity has a normal shape.

The experience: The procedure can cause cramping, ranging from mild discomfort to significant pain. Your clinic may suggest taking a painkiller beforehand. The discomfort typically subsides quickly after the procedure.

Why it matters: Blocked tubes prevent sperm and egg from meeting naturally. If tubes are blocked, IVF may be necessary to bypass them.

Transvaginal Ultrasound

What it is: An internal ultrasound using a wand inserted into the vagina.

What it shows: Your ovaries (including follicle counts and any cysts), your uterus (including fibroids, polyps, or structural variations), and your uterine lining thickness.

Why it matters: This is the workhorse of fertility imaging, used both for baseline assessment and for monitoring during treatment.

Sonohysterogram (SIS or Saline Infusion Sonography)

What it is: An ultrasound performed while saline is injected into the uterus.

What it shows: A more detailed view of the uterine cavity than a standard ultrasound, identifying polyps, fibroids, or adhesions.

When it is used: If something abnormal is suspected on regular ultrasound, or before certain treatments.

Hysteroscopy

What it is: A thin camera inserted through the cervix to directly visualise the inside of the uterus.

When it is used: When imaging suggests a problem that needs confirmation or treatment. Polyps and some fibroids can be removed during the same procedure.

Tests for Men

Male fertility testing is straightforward in some ways and underutilised in many couples' journeys. A semen analysis should happen early in the process, not as an afterthought.

Semen Analysis

What it measures: The fundamental test of male fertility, assessing:

• Volume: Amount of ejaculate (1.4ml or more)
• Concentration: Sperm per milliliter (16 million/ml or more)
• Total count: Total sperm in the sample (39 million or more)
• Total motility: Percentage moving (42% or more)
• Progressive motility: Percentage swimming forward (30% or more)
• Morphology: Percentage normally shaped (4% or more by strict criteria)

These are the World Health Organization's 2021 reference values, which NICE also uses. Results below them make conception less likely but don't mean pregnancy is impossible.

How it is done: A sample is collected through masturbation, typically at the clinic or at home if delivered promptly (labs usually need it within an hour). Abstinence of 2-7 days beforehand is recommended.

Important context: Sperm counts vary significantly between samples. An abnormal result should be confirmed with a repeat test, ideally about 3 months later, or as soon as possible if no sperm or very few sperm were found.

Additional Male Tests

If semen analysis is abnormal, further testing may include:

Hormone testing: FSH, LH, testosterone, prolactin, and thyroid function to identify hormonal causes.

Genetic testing: Karyotype analysis, Y-chromosome microdeletion testing, or cystic fibrosis gene testing, mainly if there are no sperm or very few sperm, or a blockage is suspected.

Scrotal ultrasound: To identify varicocele (enlarged veins), tumours, or structural issues.

Post-ejaculatory urinalysis: If semen volume is low, checking for sperm in urine can diagnose retrograde ejaculation.

Understanding Your Results

Test results arrive as numbers, but interpreting them requires context.

Numbers Are Not Destiny

A low AMH does not mean you cannot get pregnant. An elevated FSH does not mean treatment will not work. Abnormal sperm parameters do not mean fatherhood is impossible.

These tests identify potential challenges and help guide treatment. They are tools for decision-making, not crystal balls.

Results Should Be Interpreted Together

No single test tells the whole story. Doctors look at patterns:

• AMH, FSH, and AFC together give a fuller picture of ovarian reserve than any single test
• Hormone levels need to be interpreted in context of your cycle day and symptoms
• A blocked tube matters differently depending on whether the other tube is open

Reference Ranges Vary

Different labs use different reference ranges. "Normal" on one report might be flagged as borderline on another. Always discuss results with your doctor rather than comparing to ranges you find online.

Test Results Can Change

Ovarian reserve declines with age, but month-to-month variation exists. Sperm parameters fluctuate significantly. A result today is a snapshot, not a permanent label.

What Happens After Testing

Once testing is complete, you will meet with your doctor to review results and discuss next steps.

If Everything Looks Normal

This is good news, but can feel frustrating if you have been struggling to conceive. "Unexplained infertility" is a real and fairly common diagnosis. Treatment options still exist.

If Something Is Identified

Finding a cause, while potentially disappointing, often opens treatment pathways. Blocked tubes point toward IVF. Low sperm count might benefit from ICSI. Hormonal imbalances may be correctable with medication.

Creating a Plan

Your doctor will recommend next steps based on your complete picture: your results, your age, how long you have been trying, and your personal goals. This might be continued trying naturally, starting medication, or proceeding to IVF or IUI.

Preparing for Testing

A few practical tips to make the process smoother:

Keep track of your cycles. Know when your period starts so you can schedule day 2-4 tests appropriately.

Ask about preparation. Some tests require fasting, specific timing, or avoiding intercourse beforehand.

Bring your partner. Testing should involve both partners from the beginning.

Write down questions. Consultations can feel overwhelming. Having questions written down ensures you get the information you need.

Give yourself grace. Testing is emotionally challenging. It is okay to feel anxious, sad, hopeful, or all of these at once.

Key Takeaways

• Ovarian reserve testing (AMH, FSH, AFC) measures egg quantity, not quality, and doesn't predict natural conception. Low reserve does not mean pregnancy is impossible.

• Hormone testing identifies treatable imbalances affecting ovulation.

• Anatomical tests (HSG, ultrasound) check that physical structures are functioning properly.

• Semen analysis should happen early in the process and abnormal results should be confirmed with repeat testing.

• Results should be interpreted together by your doctor, not in isolation based on internet searches.

• Testing provides information for decision-making, not predictions about your future.

Sources

• NICE NG257: Fertility problems: assessment and treatment (March 2026) (checked October 2026)
• ASRM: Testing and interpreting measures of ovarian reserve, a committee opinion (2020) (checked October 2026)
• ASRM: Prevention of moderate and severe ovarian hyperstimulation syndrome, a guideline (2024) (checked October 2026)
• ASRM: Definition of infertility, a committee opinion (2023, PDF) (checked October 2026)
• ACOG: Evaluating infertility (checked October 2026)
• Summary of the 2023 international evidence-based guideline for PCOS. Med J Aust 2024 (checked October 2026)
• University Hospitals Birmingham NHS: Diagnostic semen analysis (WHO 6th edition methods) (checked October 2026)

This content is for educational purposes only and should not replace professional medical advice. Test results require interpretation by a qualified healthcare provider who understands your complete medical picture.