PGT-A Testing: Should You Test Your Embryos Before Transfer?
Preimplantation Genetic Testing for Aneuploidy — PGT-A — has become one of the most discussed topics in IVF. Supporters say it dramatically improves success rates and reduces miscarriage. Critics argue it may discard viable embryos and adds unnecessary cost. Here is what the evidence actually shows.
What PGT-A Does
After eggs are fertilized and allowed to develop to the blastocyst stage (Day 5–7), a small number of cells are biopsied from the outer shell of the embryo (the trophectoderm). These cells are sent to a genetics lab, where they are analyzed for chromosomal count.
A normal embryo has 46 chromosomes (euploid). An embryo with the wrong number of chromosomes (aneuploid) is unlikely to implant — and if it does, it commonly results in miscarriage or chromosomal conditions like Down syndrome.
PGT-A tells you which embryos are chromosomally normal before transfer.
The Case For PGT-A
Higher success per transfer. Transferring only euploid embryos gives a per-transfer live birth rate of 60–70% for most age groups — significantly higher than untested embryo transfers.
Fewer miscarriages. The majority of early miscarriages are caused by chromosomal abnormalities. Selecting euploid embryos substantially reduces this risk.
Shorter time to pregnancy. Rather than transferring embryos and waiting to see what happens, PGT-A directs treatment toward the embryos most likely to work.
Especially valuable after 37. As women age, a higher proportion of embryos become aneuploid. At 40, roughly 70–80% of embryos are chromosomally abnormal. PGT-A helps identify the viable minority.
The Case Against (Or: When It May Not Be Necessary)
Under 35 with good prognosis. Younger patients produce more euploid embryos naturally. The benefit of PGT-A may be smaller — and the added cost (,000–,000) may not be justified.
Limited embryos. If you only have 1–2 blastocysts, testing could leave you with nothing to transfer. Many clinicians prefer to proceed directly to transfer in these cases.
False positives exist. Mosaic embryos — those with a mix of normal and abnormal cells — may be misclassified. Some mosaics can lead to healthy pregnancies. PGT-A results are probabilistic, not absolute.
Cost. PGT-A adds significant expense that insurance rarely covers fully.
Who Benefits Most From PGT-A
- Women over 37–38
- Patients with recurrent pregnancy loss (2+ miscarriages)
- Patients with prior failed IVF cycles with untested embryos
- Those who want to minimize the time and emotional toll of unsuccessful transfers
- Patients with a known chromosomal translocation or structural rearrangement
The Bottom Line
PGT-A is a powerful tool — but it is not right for every patient. The decision should be made in consultation with your physician, weighing your age, embryo count, history, and goals.
What it is not: a guarantee. Even euploid embryos do not always implant. It improves odds; it does not control them.
Ask your fertility specialist whether PGT-A makes sense for your specific situation during your next consultation.