Should You Have PGT-A? What the Evidence Says

For most patients, no. The ASRM committee opinion on the use of PGT-A concludes that "the routine use of blastocyst biopsy with aneuploidy testing in all infertile patients undergoing IVF treatment cannot be recommended", finding no consistent improvement in overall live birth rates and describing the value of PGT-A in lowering miscarriage risk as unclear. The HFEA reaches a similar conclusion on live birth, rating PGT-A red for improving the chance of having a baby, though it rates it green for reducing miscarriage. Where there is a case, it is narrower than the marketing suggests, and this article sets out where.

What is PGT-A?

PGT-A checks whether an embryo has the correct number of chromosomes. An embryo with extra or missing chromosomes has aneuploidy, which is a common cause of failed implantation and early miscarriage.

It is distinct from the other two forms of testing. PGT-M looks for one specific inherited single-gene condition the parents are known to carry; PGT-SR looks for structural rearrangements such as translocations. Both test for something already identified, and the evidence discussion below does not apply to them. Our article on the difference between the three covers this.

How is it done?

1. Embryos are cultured to the blastocyst stage, usually day five or six.
2. A few cells are taken from the trophectoderm, the part that goes on to form the placenta rather than the baby.
3. The embryos are frozen while the cells are analyzed.
4. Results guide which embryo is selected for transfer.

The biopsy is an additional procedure on the embryo. Discuss its specific risks with your specialist as part of consenting, rather than treating it as risk-free.

What does the evidence show?

This is the part that matters, and it is more nuanced than either "it works" or "it does not".

• Younger patients with a favorable prognosis: multiple recent trials showed no benefit. This is the group most often sold PGT-A as an upgrade.
• Women aged 35 to 40, and 40 to 43: limited evidence suggests possible benefit, from post-hoc analysis and observational data rather than from trials designed to answer the question.
• Recurrent pregnancy loss: some database analysis found higher live birth rates, but ASRM concludes definitive evidence of benefit in this group is lacking.
• Donor egg cycles: ASRM states the totality of evidence argues against routine use.
• Male factor infertility: ASRM states PGT-A should not be used for this purpose alone.
• Miscarriage: the two regulators differ. HFEA rates PGT-A green for reducing miscarriage; ASRM describes the value as unclear. Both agree it does not consistently improve live birth rates.

What are the trade-offs?

• Cost. PGT-A adds significantly to a cycle.
• Fewer embryos to transfer. The HFEA's point is that PGT-A is a selection tool that reduces the number of embryos available, which is why it may lower rather than raise the chance of a baby. If you have few embryos, this matters most.
• Inconclusive and mosaic results, which create difficult decisions rather than resolving them.
• An additional procedure on the embryo.

Against those, where it helps, it can avoid the transfer of an embryo that would not have implanted or would have miscarried, and shorten the route to a viable pregnancy.

What to ask before agreeing

• Which patient group am I in, and what does the evidence show for that group specifically?
• How many embryos do I have, and what happens if none are suitable after testing?
• What does it add to the cost?
• What happens if a result is inconclusive or mosaic?

We at Millennium IVF Clinic will go through whether PGT-A applies in your case. You can arrange a consultation with our team.

Frequently asked questions

Will PGT-A improve my chance of a baby?

Not for most patients on the current evidence. ASRM found no consistent improvement in live birth rates and does not recommend routine use; HFEA rates it red on that question and notes it may reduce the chance.

Does PGT-A prevent miscarriage?

The regulators differ. HFEA rates it green for reducing miscarriage; ASRM describes the evidence as unclear. Neither finds it improves live birth rates.

What is a mosaic embryo?

One where the biopsy finds both normal and abnormal cells. These results are genuinely difficult to act on, and it is worth asking in advance how your clinic handles them.

Is PGT-A the same as an NIPT test in pregnancy?

No. PGT-A tests embryos before transfer. Screening during pregnancy is separate and is not replaced by having had PGT-A.