What Is Preimplantation Genetic Testing (PGT) and How Does It Work?

In IVF, preimplantation genetic testing (PGT) is a method used to examine embryos prior to their transfer into the uterus. It aids in locating chromosomal or genetic issues that can interfere with conception.

Preimplantation genetic screening and preimplantation genetic diagnosis are other terms you could hear. These are similar to embryo genetic testing, depending on whether the focus is on a specific illness or overall chromosomal health.

The main reason is to improve the chances of a healthy pregnancy with IVF. PGT is an option for couples when there is:

• A chromosomal problem-related history of miscarriages.
• A family history of inherited disorders that can be detected using PGT-M.
• Prior unsuccessful IVF efforts.
• Risks of embryonic chromosomal disorders associated with maternal age.

To put it simply, PGT aids in the selection of embryos that are most likely to produce a healthy pregnancy. It gives some families peace of mind that the likelihood of hereditary disorders being passed down is decreased.

The PGT procedure happens as part of an IVF cycle:

1. Embryo creation: Eggs are fertilized with sperm in the lab.
2. Embryo biopsy: A few cells are gently removed from each embryo once it reaches the blastocyst stage.
3. Genetic analysis: These cells are tested for chromosomal abnormalities or genetic disorders.
4. Embryo selection: Only embryos that test normal are considered for transfer.

This process is sometimes referred to as PGT embryo testing or preimplantation genetic diagnosis.

There are different types of preimplantation genetic testing:

PGT-A (Aneuploidy testing)

The purpose of this test is to seek any chromosomal abnormality in the embryo, including those that lack or have additional chromosomes. A frequent cause of miscarriages and failed IVF rounds is aneuploidy. PGT-A testing aids in selecting embryos with the correct number of chromosomes, resulting in a higher rate of successful pregnancy.

PGT-M (Monogenic disorders)

PGT-M is applicable in cases where one or both parents possess a known genetic mutation. It pre-tests embryos for single-gene disorders such as cystic fibrosis, thalassemia, or sickle cell disease. By picking out the embryos that are not mutated, families reduce the chance of transmitting these conditions to their child.

PGT-SR (Structural rearrangements)

This is a test to be performed on spouses in a situation where one of the parents has a structural alteration in their chromosomes, such as an inversion or translocation. These may cause unbalanced embryos and frequent miscarriages. The use of PGT-SR assists in determining embryos that will have normal chromosome complements and are likely to lead to a successful, healthy pregnancy.

Using PGT, IVF-created embryos are assessed to screen against:

• Chromosomal abnormalities: Additional chromosomes or missing or abnormal chromosomes are found when using PGT-A testing.
• Single-gene diseases: Inherited diseases, including sickle cell disease, thalassemia, or cystic fibrosis.
• Structural rearrangements: Chromosomal aberrations that can lead to effects on the health of an embryo.

Some benefits of getting preimplantation genetic testing are:

• Increasing reproductive possibilities: The success of IVF is boosted when only chromosomally normal embryos are chosen.
• Reduced risk of miscarriage: PGT can identify many miscarriages that are associated with chromosomal abnormalities.
• Genetic disorder screening: Families with a history of inherited disorders can minimize the likelihood of passing them on.
• Reduced unsuccessful IVF: Couples can save on repeated unsuccessful IVFs by transferring only viable embryos.
• Informed choice: Parents become informed and self-confident about the processes of transferring embryos.

Although a good idea, there are certain restraints with PGT:

• No guarantee: Pregnancy is not guaranteed after PGT, and there are other variables that can influence outcomes.
• Cost: The practice comes with a hefty price tag that accompanies IVF, and prices fluctuate greatly.
• Loss of embryos: Embryos may be destroyed when they are detected to have an abnormality, which is both emotionally upsetting and an ethical issue.
• Precision: Although a trustworthy test, no genetic test has 100 percent precision.
• Ethical arguments: The ethics of preimplantation genetic testing revolve around the notion of embryo selection, the fear of misuse not involving medical necessity, and issues regarding decreasing variety because of the selection of certain genetic traits.

Discussing the preimplantation genetic testing pros and cons with a professional can help you make an appropriate decision about this type of testing.

Preimplantation genetic tests are projected to be costly since they require embryo biopsy and extensive laboratory work. The PGT test cost is usually charged out on an embryo-by-embryo basis and may not be covered by insurance products.

The total cost is based on:

• Embryos tested
• Type of testing
• Technology and the clinic employed
• IVF cycle requirements
• Medical history in the family
• Patient factors include age and the number of viable blastocysts.

It is thus advisable to consult with your fertility doctor, who can present to you a more precise breakdown depending on your treatment plan.

Preimplantation genetic testing doesn’t promise a pregnancy, but it helps guide decisions by checking embryos for chromosomal issues, inherited gene disorders, or structural rearrangements.

If you’re thinking about this treatment, book an appointment at ART Fertility Clinics. We operate our own genetics lab and embryology facilities, and are recognized for our high success rates and clear, ethical approach to treatment.

What is preimplantation genetic testing, and how does it impact IVF outcomes?

In IVF, preimplantation genetic testing (PGT) is applied to examine the embryos prior to transfer. It tests chromosomal abnormalities and particular genetic disorders. PGT can be used to increase the likelihood of implantation and decrease the possibility of miscarriage, as well as decrease the risk that an inherited disease will be transferred down the line of descent.

Does PGT testing tell you gender?

Yes, because PGT views all chromosomes, the sex chromosomes of the embryo (XX or XY) can be identified. In most countries, however, PGT use remains limited or prohibited, ethically, to gender-only selection.

How many embryos pass PGT testing?

The number varies. Younger patients usually have a higher percentage of chromosomally normal embryos compared to older patients. On average, not all embryos pass, as some show chromosomal abnormalities or genetic issues.

Is PGTA required for IVF?

No, PGT-A is not required for IVF. Many couples conceive through IVF without it. PGT-A is usually recommended when there’s advanced maternal age, repeated miscarriages, or previous failed IVF cycles.

How long does it take to get PGT-M results?

PGT-M testing results usually take about 1–2 weeks, depending on the clinic and laboratory. This timeline allows doctors to analyse the cells removed from the embryo before deciding on transfer.