To Test or Not to Test: What the Evidence Actually Says About PGT

You’re sitting across from your reproductive endocrinologist, and somewhere between the medication protocols and the retrieval timeline, they slide a new term into the conversation: PGT-A. Preimplantation genetic testing for aneuploidy. They explain that it screens your embryos for chromosomal abnormalities before transfer, and that it can help identify which embryos have the best shot. It sounds like an obvious yes. Why wouldn’t you want the most information possible?

Then you see the price tag. Then you start Googling. And suddenly you’re deep in a rabbit hole of conflicting headlines, fertility forum debates, and a growing sense that the answer to “should I do PGT?” is a lot less straightforward than your clinic made it sound.

You’re not imagining that. The medical community itself is genuinely divided on this one, and understanding where the science actually stands can help you make a decision that’s right for your situation, not just the default one.

PGT stands for preimplantation genetic testing, a group of lab techniques used to analyze embryos created through IVF before they’re transferred to the uterus. There are a few types, but the one you’ll hear about most is PGT-A (the “A” stands for aneuploidy), which checks whether an embryo has the right number of chromosomes.

A normal human cell has 46 chromosomes. An embryo with too many or too few (called an aneuploid embryo) is more likely to fail to implant, end in miscarriage, or in rare cases, result in a genetic condition like Down syndrome. PGT-A aims to catch these abnormalities early so your doctor can prioritize transferring embryos with the expected chromosome count (called euploid embryos).

The process works like this: around day 5 or 6 of embryo development, an embryologist removes a small cluster of 5 to 10 cells from the outer layer of the blastocyst (the part that will become the placenta, not the baby itself). Those cells get sent to a genetics lab for analysis, and results typically come back within one to two weeks. In the meantime, your embryos stay frozen.

There’s also PGT-M (for monogenic conditions), which screens for specific inherited diseases like cystic fibrosis or sickle cell disease, and PGT-SR (for structural rearrangements), which looks for chromosomal translocations. These are more targeted, and your doctor would recommend them based on your family history or carrier screening. PGT-A is the broad screening tool, and it’s the one at the center of a very active debate.

There are real, evidence-backed reasons doctors recommend PGT-A for certain patients. The core argument is simple: if you can identify the embryos most likely to result in a healthy pregnancy, you can reduce the number of failed transfers and miscarriages, both of which are physically and emotionally costly.

The data supports this in specific situations. A 2024 analysis found that PGT-A transfers resulted in significantly higher live birth rates per transfer compared to non-PGT-A frozen embryo transfers (50.6% versus 35.8%). For patients aged 35 to 37, PGT-A was associated with a slightly improved cumulative live birth rate (risk ratio: 1.04), and for those aged 38 to 40, the benefit was more pronounced (risk ratio: 1.14).

As Scientific American explains, ruling out the embryos most likely to result in miscarriage helps reduce the number of IVF cycles required to achieve a successful pregnancy. That’s significant because every cycle is expensive and, like miscarriage, physically and emotionally taxing.

PGT-A can also support single embryo transfer decisions. If you have multiple embryos and want to avoid the risks of twins, knowing which embryo is euploid can give you and your doctor more confidence in transferring just one.

Here’s where it gets nuanced, and where you deserve the full picture.

The ASRM’s 2024 committee opinion, the most authoritative guidance in U.S. reproductive medicine, states plainly: “The value of PGT-A as a routine screening test for all patients undergoing in vitro fertilization has not been demonstrated.” This replaced their earlier 2018 guidance and reflects a growing body of evidence that PGT-A may not help everyone the way it’s often presented.

The biggest piece of evidence? A landmark trial published in the New England Journal of Medicine studied over 1,200 patients at 14 fertility centers. The results: live births occurred in 77.2% of the PGT-A group compared to 81.8% in the conventional IVF group. In other words, for patients with a good prognosis, PGT-A didn’t improve outcomes, and the conventional IVF group actually did slightly better.

For younger patients, the picture is similar. Data show that in patients under 35, PGT-A was associated with a slightly lower cumulative live birth rate (67.3% versus 68.6%) compared to no testing.

Then there’s the mosaicism question. When cells are biopsied from an embryo, the sample may not represent the whole. Embryos flagged as “mosaic,” meaning they contain a mix of normal and abnormal cells, were once routinely set aside. But a growing body of research, including a 2024 study in Genes, has documented over 488 healthy babies born from mosaic embryo transfers. The ASRM now acknowledges that transfer of mosaic embryos is a “relatively safe option” with “low or minimal risk” beyond the background risk for any pregnancy. That means some embryos that PGT-A would have flagged could have become healthy pregnancies, and some patients may have discarded embryos that would have been fine.

This is not a theoretical concern. As STAT News reported, clinicians and researchers have said that many providers have good intentions, but are “still offering patients an unproven, expensive, and possibly risky procedure.”

PGT-A can typically add $4,000 to $10,000 to an IVF cycle in the U.S., covering the embryo biopsy fee (usually around $2,500) plus the genetics lab analysis (another $2,500 or so). Most insurance companies classify it as elective, so the cost usually falls entirely to the patient.

Despite the ASRM’s cautious stance, usage has surged. Data from the Society for Assisted Reproductive Technology show the proportion of IVF cycles using PGT climbed from 14% in 2014 to 44% in 2019, a threefold increase in just five years. At many clinics, it’s now presented as standard rather than optional.

That gap between the official guidance and clinical practice has drawn scrutiny. In 2025, TIME reported that nearly 700 IVF patients filed class-action lawsuits against several PGT-A testing providers, alleging that patients were misled about the accuracy and utility of the test. The lawsuits claim that some patients discarded embryos based on results that may have been inaccurate, a devastating outcome for anyone in the fertility world.

This doesn’t mean PGT-A is a scam. It does mean that how it’s presented to patients, and whether the nuances are adequately explained, matters enormously.

If you’ve spent any time in IVF communities online, you know PGT is one of the most debated topics out there. On forums like Mumsnet and r/IVF, patients share stories that capture the full spectrum of outcomes: some describe the relief of transferring a euploid embryo on the first try and getting a positive result. Others describe the heartbreak of getting back results showing no normal embryos out of an entire retrieval, and the particular sting of wondering whether some of those embryos could have worked anyway.

One patient on a fertility forum described having three egg collections at age 41, receiving 10 embryos for testing, and learning all were aneuploid. She never even attempted a transfer. “It left me with a sad feeling,” she wrote, “despite having had four chemical pregnancies.”

That kind of story illustrates the core tension: PGT-A can spare you the grief of a failed transfer, but it can also take options off the table that might have had a different outcome. The emotional weight of that trade-off is real, and it doesn’t get discussed enough in the clinic.

Technically, no. The ASRM does not recommend PGT-A as routine for all IVF patients. It’s not considered standard of care in the way that, say, monitoring follicle growth during a stimulation cycle is.

But in practice? At many clinics, it’s treated that way, especially for patients over 35 or those with a history of pregnancy loss. And that disconnect between guideline and practice is exactly why this conversation matters.

The patients most likely to benefit from PGT-A, based on current evidence, include those who are 38 or older, those with recurrent miscarriage or implantation failure, and those with a known chromosomal translocation. For younger patients with a good prognosis and plenty of embryos, the evidence is much less clear, and the ASRM explicitly notes that PGT-A has not demonstrated value as universal screening.

If your clinic recommends PGT-A, you don’t have to say yes or no on the spot. Here are some questions that can help you figure out whether it makes sense for you:

PGT-A is a powerful tool, but it’s a tool, not a guarantee, and not a default. The science supports its use for specific patient groups while also raising real questions about whether it’s being offered too broadly, too confidently, and without enough transparency about its limitations.

If your doctor recommends it, that doesn’t mean it’s wrong for you. And if you choose not to do it, that doesn’t mean you’re being reckless. What matters is that you have the full picture: the data, the debate, and the acknowledgment that this decision belongs to you.

You’re allowed to ask hard questions. You’re allowed to want more time. And you’re absolutely allowed to make a different choice than the person in the waiting room next to you.