PGT-A genetic testing can identify chromosomally normal embryos before transfer — but is it right for everyone? Here's what you need to know.
What Is PGT-A and Why Are More Couples Asking About It?
If you have been through one or more IVF cycles, you may have heard your doctor mention PGT-A — Preimplantation Genetic Testing for Aneuploidies. It sounds complex, but the idea behind it is straightforward: before transferring an embryo to the uterus, a few cells are biopsied and analysed to check whether the embryo has the correct number of chromosomes.
A chromosomally normal embryo is called euploid. An embryo with an abnormal chromosome count — either too many or too few — is called aneuploid. Aneuploid embryos are the leading cause of failed IVF transfers, early miscarriage, and conditions like Down syndrome. PGT-A is designed to help identify which embryos give you the best possible chance of a healthy pregnancy.
At Iswarya Fertility, we believe that every patient deserves to understand not just what a test is, but whether it is genuinely useful for their situation. So let us walk you through the real picture.
How Does PGT-A Actually Work?
PGT-A is performed during an IVF cycle, after your embryos have been grown in the laboratory for five to six days and reached the blastocyst stage. At this point, an embryologist carefully removes a tiny sample of cells from the outer layer of the embryo — the part that will eventually become the placenta, not the baby itself. This means the embryo remains intact and unharmed.
The cell sample is sent to a specialist genetics laboratory where the chromosomes are mapped. Results are typically available within one to two weeks. Your embryos are frozen while you wait, and only those confirmed as euploid are considered for transfer in a subsequent frozen embryo transfer cycle.
What PGT-A Can and Cannot Tell You
- It can identify: Embryos with the wrong number of chromosomes (trisomies, monosomies, and other large structural errors).
- It cannot identify: Single-gene disorders (that requires a different test called PGT-M), very small chromosomal changes, or all possible causes of implantation failure.
- It does not guarantee pregnancy: A euploid embryo still needs a receptive uterine lining, good endometrial health, and other favourable factors to implant successfully.
Understanding these boundaries is important so that your expectations going into testing — and transfer — are grounded in reality.
Who Is Most Likely to Benefit from PGT-A?
PGT-A is not a one-size-fits-all recommendation. Research and clinical experience suggest it offers the most meaningful benefit in specific groups of patients.
Women Over 35
The rate of chromosomal abnormalities in embryos rises significantly with age. By 40, more than half of all embryos produced during an IVF cycle may be aneuploid. For women in this age group, PGT-A can meaningfully improve the efficiency of the IVF process by helping identify which embryos are worth transferring — reducing the emotional and physical toll of repeated failed cycles.
Couples with Recurrent Miscarriage
If you have experienced two or more pregnancy losses, chromosomal abnormalities in the embryo are a common underlying cause. PGT-A can help break this painful cycle by ensuring only chromosomally screened embryos are transferred.
Patients with Repeated Implantation Failure
If good-quality embryos have been transferred in previous cycles without success, PGT-A can help determine whether chromosomal abnormality may have been a contributing factor — and prioritise embryos that are more likely to implant.
Carriers of Chromosomal Rearrangements
Some individuals carry balanced chromosomal rearrangements that do not affect their own health but significantly increase the risk of producing aneuploid embryos. PGT-A is strongly recommended in these cases.
The Debate Around PGT-A for All IVF Patients
You may have heard that some clinics offer PGT-A routinely to all IVF patients, regardless of age or history. This is an area of active discussion in the fertility medicine community, and the evidence is more nuanced than it might first appear.
For younger women under 35 with no history of miscarriage or failed cycles, the benefits of PGT-A are less clearly established. Most embryos in this group are chromosomally normal to begin with, so widespread screening may not dramatically improve cumulative success rates — and it does add cost and the need for embryo freezing.
Additionally, some embryos initially flagged as abnormal through PGT-A have been found to have a degree of mosaicism — where some cells are normal and others are not. The clinical significance of mosaic embryos is still being studied, and in some cases, transferring a mosaic embryo under careful clinical guidance has resulted in healthy pregnancies. This is a conversation worth having in depth with your specialist.
What Does the PGT-A Process Mean for Your IVF Timeline?
Choosing PGT-A does extend your overall IVF journey slightly, since all embryos must be frozen while testing is completed. However, many patients and clinicians now prefer this freeze-all and transfer later approach regardless, as it gives the uterus time to recover from stimulation before transfer — which can support better implantation outcomes.
The practical steps look like this:
- Egg retrieval and fertilisation as standard in IVF
- Embryos grown to blastocyst stage over five to six days
- Embryo biopsy performed by a trained embryologist
- Embryos vitrified (flash-frozen) and stored
- Genetic results reviewed with your doctor
- Euploid embryo(s) transferred in a subsequent frozen embryo transfer cycle
At Iswarya Fertility, our embryology team is trained in blastocyst biopsy techniques that prioritise the integrity of your embryos throughout this process. We work closely with accredited genetics laboratories to ensure accurate results and clear interpretation.
Making the Right Decision for You
The decision to pursue PGT-A is deeply personal and should be made with full information, not pressure. Your age, medical history, number of embryos available, previous cycle outcomes, and personal values all matter. Some couples find the additional clarity invaluable — it gives them confidence going into a transfer. Others, particularly younger patients with strong embryo numbers and no history of loss, may reasonably choose to proceed without it.
What matters most is that the decision is yours, made with honest guidance from your care team.
If you are navigating these questions and wondering whether PGT-A could make a difference in your fertility journey, we would love to speak with you. The specialists at Iswarya Fertility are here to help you understand every option — not just what is possible, but what makes sense for you specifically. Book a consultation today and let us help you move forward with clarity and confidence.