The key tests involved in IVF

14 April 2025

George Bakolas

The key tests involved in IVF

Deciding to start IVF is a significant step, and if you’ve been trying to conceive (TTC) for a while, you might feel a mix of emotions – hope, anxiety, and perhaps even relief at having a clear plan.

We asked Mr George Bakolas, fertility specialist, obstetrician, and gynaecologist at The Evewell West London, to guide you through the tests commonly performed before and during the IVF process, explaining their purpose and what you can expect.

Your consultant may recommend additional tests based on your overall health and fertility history – we touch on a few below – but this article mainly focuses on standard tests you’d expect to have during a standard IVF cycle.

Legal tests before starting IVF

The HFEA requires all clinics to ensure all patients have up-to-date virology blood screenings before any licensed fertility treatment. We can help you check if any existing results you have meet the requirements.

These tests include:

• Hep B core antibody
• Hep B surface antigen
• Hep C
• HIV
• Rubella
• HTLV I+II

While these tests are standard and a legal requirement, there are additional tests your doctor may recommend further investigations based on your unique medical history and circumstances.

Why are necessary tests before IVF?

IVF is a highly individualised treatment, and no two journeys are the same. The tests conducted before or during your Initial Consultation provide critical insights into factors that could influence the outcome of your cycle.

These include blood tests for ovarian function, ultrasound scans and if having treatment with a male partner, sperm health.

It’s a combination of these tests – alongside your general health and fertility history – that will show us your fertility potential and help us create a personalised IVF treatment plan, giving you the best possible chance of success of a live birth and giving you options for additional children in the future.

AMH blood test

Anti-Mullerian hormone (AMH) gives us an indication of your ovarian reserve (or egg count). It’s a hormone made by the sacs in your ovaries that go on to produce an egg.

It’s a blood test that takes place in our clinics. One of our nursing team takes it at least a few days before your consultation, so we have the results back in time. You’ll get these results back in your consultation to discuss them with your doctor.

Everyone will have different AMH results, but what we all have in common is that this declines as we get older. So, by testing your AMH and plotting it against the ‘normal’ values for your age, our consultants will gain insight into what your ovarian reserve looks like in comparison to someone else the same age.

Your AMH level will help guide our recommendations for your personal circumstances, giving us an indication of whether (or not) you need to move forward with fertility treatment or preservation, how quickly, and what treatment we’d recommend. It also helps us decide which medications are most appropriate and what the anticipated results could be if you were to have treatment.

Ultrasound scan

A transvaginal (internal) ultrasound scan looks at your uterus and ovaries in more detail to see if there are any structural issues or conditions, such as PCOS or endometriosis, that could impact your gynaecological health or fertility goals.

We also use this scan to count the number of follicles that we see in your ovaries; these follicles are fluid-filled sacs that have the potential to go on to create an egg. Like your AMH levels, these numbers will vary from person to person, but also decline as we get older.

We use your AMH blood test result and an ultrasound scan to give us a clearer picture of your reproductive potential and guide the choice of medication protocols during treatment.

An ultrasound with an experienced consultant may well highlight issues you weren’t aware of that we can help treat, and that may mean you don’t need fertility treatment.

Semen analysis

Semen tests and their results are crucial in our planning of treatment as they can rule specific fertility treatments out, or help our consultants make recommendations for treatments to help with male factor infertility, such as ICSI.

A semen analysis looks at several key sperm factors to give you an indication of sperm health. These are:

1. Sperm count – The number of sperm in a sample is the parameter that most people have heard about. A high sperm count gives a better chance of one sperm reaching the egg naturally than a lower one does. A low sperm count would also direct us when making treatment recommendations.

2. Motility – the way the sperm move in the sample, whether they’re swimming, moving or still. Sperm that are swimming well are more likely to reach and fertilise an egg than those that aren’t.

3. Morphology is the shape of the sperm. Sperm cells should have a head, a midpiece, and a tail; if any of these parts are malformed or missing, this will impact the sperm’s ability to fertilise an egg naturally.

If the results show poor levels of any of the above, don’t panic! There are things we can do to help.

Unlike eggs, sperm cells are regenerated every three months. This means that diet and lifestyle changes, treating infections and taking supplements can have a massive effect on some sperm factor issues.

Should this be relevant to you, we can make personalised recommendations to help improve your chances of conception.

Remember: it takes a sperm AND an egg to create a baby!

Optional testing to increase outcomes: genetic testing

Depending on your age, fertility history and any previous treatment or complications, genetic testing can be an essential consideration for people to consider. The two main types of testing include PGT-A and PGT-S.

While genetic testing doesn’t change the inherent quality of embryos, it helps refine the selection process. Instead of undergoing multiple transfers with embryos that may never develop into a viable pregnancy, genetic testing helps select embryos with the highest chance of success from the outset.

Using PGT-A in an IVF cycle

PGT-A screens embryos for chromosomal abnormalities. Human embryos should have 46 chromosomes – 23 from the egg and 23 from the sperm. Embryos with the wrong number of chromosomes are often unable to implant, may result in miscarriage, or lead to genetic conditions such as Down Syndrome.

By transferring only genetically normal (euploid) embryos, we can:

• Reduce the time to pregnancy: PGT-A helps select embryos with the highest chance of success from the outset, avoiding multiple embryo transfers with embryos that were not compatible with life
• Minimise emotional and physical strain: knowing that the embryos being transferred are chromosomally normal reduces the uncertainty and potential heartbreak associated with unsuccessful transfers or miscarriages

However, it’s important to manage expectations. While PGT-A can significantly increase the likelihood of a successful transfer, it does not guarantee a live birth. Other factors, such as the uterine environment and overall health, also play a role in the success of IVF.

Genetic carrier screening (PGT-S)

PGT-S is particularly relevant for those who are aware of a family history of genetic disorders or belong to ethnic groups with higher prevalence rates for certain conditions.

PGT-S identifies carriers of genetic conditions such as:

• Cystic fibrosis: a life-limiting condition affecting the lungs and digestive system.
• Sickle cell anaemia is a blood disorder that can cause severe pain, infections, and complications.

By using genetic testing in IVF, embryos can be screened to ensure only those without the condition are transferred. This reduces the likelihood of passing on genetic disorders, providing peace of mind for the parents.

We understand that introducing genetic testing might seem like one more complex layer. However, these tests are tools designed to provide clarity, reduce uncertainty, and optimise your chances of success.

Unique to The Evewell is that every patient has an embryologist consultation before starting IVF, giving you the opportunity to ask any questions related to additional testing recommended by your consultant.