Preimplantation Genetic Testing (PGT): When It Is Recommended and How the Process Works

Preimplantation Genetic Testing, commonly called PGT, is an advanced reproductive technique used during an IVF cycle to examine embryos for specific genetic or chromosomal concerns before embryo transfer. At Genesiss Hospital, PGT is listed under the IVF & Advanced Reproductive Techniques section within the Male, Female Infertility & IVF speciality, alongside IVF, IUI, ICSI, egg and sperm donation, and embryo freezing.

PGT is usually considered when couples want a more informed embryo selection process because of repeated IVF failure, recurrent miscarriage, advanced maternal age, known genetic concerns, or previous abnormal embryo development. It does not replace IVF. Instead, it works as an additional laboratory step within IVF to help specialists choose an embryo with a lower risk of certain chromosomal or genetic issues for transfer. For many couples, this treatment is not only about improving pregnancy planning. It is also about reducing uncertainty during an already emotional fertility journey.

When explained clearly, PGT should not feel like a technical concept meant only for laboratory professionals. It should help patients understand three things: why the test is advised, what it can and cannot detect, and how it fits into the larger IVF process. That is exactly how this page should work for Indian fertility patients searching online with real intent.

What is Preimplantation Genetic Testing (PGT) in IVF treatment?

Preimplantation Genetic Testing is a laboratory-based embryo screening method used during an IVF cycle. After eggs are fertilized and embryos begin developing, a few cells may be carefully taken from the embryo and sent for genetic analysis. The purpose is to study whether the embryo shows certain chromosomal abnormalities or selected inherited genetic concerns before it is transferred into the uterus.

In simple words:

• IVF creates the embryo
• PGT studies the embryo before transfer
• Embryo transfer happens after the test result is reviewed

This means PGT is not a fertility treatment on its own. It is an advanced decision-support step within IVF.

Patients commonly confuse PGT with pregnancy testing or regular blood tests done during pregnancy. It is neither. PGT is done before pregnancy begins, at the embryo stage, to guide embryo selection.

Why is PGT recommended during an IVF cycle?

PGT is usually recommended when the fertility specialist feels that embryo selection needs additional genetic information before transfer. It is not necessary in every IVF cycle. In fact, many couples conceive without needing it. However, in selected cases, it can play a very important role.

Doctors may consider PGT in situations such as:

For couples who have already been through multiple fertility disappointments, this added step may help make the next IVF cycle more targeted and structured.

What are the different types of PGT and what do they mean?

This is one of the most important sections because many patients hear the term PGT but do not know that it includes different testing categories.

PGT-A

PGT-A is commonly used to look for aneuploidy, which means an abnormal number of chromosomes in the embryo.

PGT-M

PGT-M is used when there is a known single-gene disorder in the family.

PGT-SR

PGT-SR may be used when one of the partners has a known structural chromosomal rearrangement.

In simple terms:

• Some PGT tests look at chromosome number
• Some look at a specific inherited condition
• Some are used when chromosomal structure is already known to be altered

Who may benefit most from PGT treatment?

Patients who may benefit include:

• Women with repeated IVF implantation failure
• Couples with recurrent pregnancy loss
• Women of advanced reproductive age
• Couples with known inherited genetic risk
• Couples who want more information before embryo transfer in selected IVF cycles

How does the PGT process work step by step?

Step 1: Ovarian stimulation and egg retrieval

Step 2: Fertilization

Step 3: Embryo development

Step 4: Embryo biopsy

Step 5: Genetic analysis

Step 6: Embryo freezing

Step 7: Embryo transfer planning

PGT treatment flow:

Does PGT improve pregnancy chances for every couple?

No. PGT does not guarantee pregnancy.

It may help improve embryo selection in selected cases, but success depends on:

• Age
• Embryo quality
• Uterine health
• Number of embryos
• Medical history

What is the difference between embryo grading and PGT?

Is PGT safe for embryos?

PGT is generally performed in advanced IVF laboratories using structured protocols. However, it should only be advised where its benefit is meaningful.

When is PGT usually not the first recommendation?

• Early fertility treatment stage
• No genetic concern
• Limited embryos
• Non-genetic fertility issue

Meet the Fertility Specialist

Dr. Divya J G
Obstetrician, Gynaecologist and IVF Specialist

When should couples consult a fertility specialist about PGT?

• Repeated IVF failure
• Recurrent miscarriage
• Known genetic disorder
• Advanced maternal age

Can PGT be combined with ICSI and embryo freezing?

Yes. A common pathway:

• IVF
• ICSI
• Embryo development
• PGT
• Freezing
• Transfer later

FAQs: