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Genetic testing

PGT-M embryo testing

Pre-implantation genetic testing for single-gene conditions - IVF with embryo selection for families facing serious inherited disease.

Key facts

At a glance

  • What it is: IVF followed by biopsy of a few cells from each embryo, testing for a specific familial condition before transfer.

  • Who it serves: couples at risk of passing on serious single-gene conditions - cystic fibrosis, Huntington’s, BRCA-related cancer risk and many others.

  • Regulation: in the UK, the HFEA licenses which conditions can be tested - the approved list runs to hundreds.

  • NHS funding: available for eligible couples within criteria (age, existing children, BMI and others) via genetics referral; criteria vary.

  • Follow-up: genetic counselling and fertility consultation together map the pathway - workup to transfer typically spans several months.

The full picture

What this test involves, and how to get it

PGT-M (pre-implantation genetic testing for monogenic disorders) lets couples who carry a serious inherited condition start a pregnancy knowing the embryo is unaffected. The pathway is IVF even for fertile couples: eggs are collected and fertilised, embryos grow five to six days to blastocyst, a few placental-line cells are biopsied from each, and a bespoke genetic test - built in advance for your family’s specific variant - identifies which embryos are free of the condition for transfer. In the UK the Human Fertilisation and Embryology Authority licenses testable conditions, a list of many hundreds spanning cystic fibrosis, spinal muscular atrophy, Huntington’s disease and inherited cancer syndromes such as BRCA; Huntington’s families can use non-disclosure approaches that avoid revealing a parent’s own status.

Honest framing helps: the test workup takes months before treatment begins, IVF success rates per cycle apply on top of the genetics, and not every cycle yields transferable embryos - counselling covers all of this alongside the alternatives (prenatal testing, donor gametes, acceptance of risk). NHS funding exists for couples meeting criteria - typically referred through clinical genetics to a licensed PGT centre - but eligibility rules (age, BMI, existing unaffected children, smoking) and waits vary by nation and region. Private PGT-M at licensed UK clinics removes the criteria but not the regulation, with costs quoted per stage and confirmed upfront. The right first step is a genetics consultation to confirm the variant is testable and map both funding routes before committing to either.

A quiet reminder

This guide is for information, not medical advice.

Your own clinician knows your history and can tell you which parts apply to you. Next review of this page: 2027-09-27.

Frequently asked

Common questions about PGT-M embryo testing.

Quick, plain-English answers to what people ask us most.

  • What is PGT-M embryo testing?

    PGT-M embryo testing is a genetic test that looks at specific DNA information relevant to a particular condition, inherited risk, or family planning question. It is usually considered when there is a personal or family history that makes this information clinically relevant. Genetic counselling is often recommended alongside testing to help you understand what a result would mean.

  • Why would someone need this test?

    This type of testing is typically used to assess carrier status, inherited risk, or a specific genetic cause for a condition already suspected on clinical grounds. It may be recommended by a GP, specialist, or fertility clinic depending on the context. The decision to test is usually made together with a healthcare professional, given the personal implications involved.

  • Do I need to prepare for this test?

    Most genetic tests only require a simple blood sample or saliva swab, with no special preparation such as fasting needed. What matters more is having a pre-test conversation, often with a genetic counsellor, about what the possible results could mean for you and your family. This helps you make an informed decision before proceeding.

  • What happens during the test?

    A blood sample or saliva swab is taken and sent to a specialist genetics laboratory for analysis. This part of the process is quick and generally painless. The laboratory work itself, including sequencing and interpretation, is what takes the most time.

  • How long do results take?

    Genetic test results generally take longer than routine blood tests, often several weeks, because of the specialised laboratory analysis and interpretation involved. Your clinician or genetic counsellor will give you a realistic timeframe when the test is arranged. Results are usually discussed with you in a dedicated follow-up appointment rather than by letter alone.

  • What do the results mean, and what happens next?

    Results are usually explained by a geneticist or genetic counsellor, who can put the finding into context and discuss any implications for you and, where relevant, your family members. Next steps vary widely depending on the specific result and may include further testing, specialist referral, or reproductive planning advice. It is normal to need time and support to process this kind of information.

  • Is genetic testing available privately, and how much does it cost?

    Yes, many genetic tests can be arranged privately, often with shorter waits than some NHS genetics pathways depending on the specific test and local services. Cost varies by provider and confirmed before booking. Private genetic counselling is usually included or available alongside testing to support you in understanding the result.

  • Is this type of test accurate?

    Modern genetic testing carried out in accredited laboratories is highly accurate for detecting the specific changes it is designed to look for. However, genetics is complex, and a result is not always straightforward to interpret in isolation - context from a genetic counsellor or specialist is important. Very rarely, further confirmatory testing may be recommended.

  • How do I book this test privately?

    You can usually arrange this through a private genetics clinic or fertility service, either with a referral or via self-referral depending on the provider. Pre-test counselling is typically arranged as part of the process.