Aneuploid embryo success rates after transfer are very low, with about 1–2% leading to a live birth, likely due to undetected mosaicism after PGT-A rather than true whole chromosome aneuploidy.
PGS (PGT-A) success rates
A 2026 study found that mosaic embryo outcomes vary by type and level, with high-level and trisomy mosaics showing lower success rates, while segmental mosaics had outcomes similar to euploids.
A 2025 study found that after a first frozen embryo transfer, experiencing an early pregnancy loss did not increase the risk of loss in the next transfer, for both euploid or untested embryos.
In a 2025 study, researchers masked mosaic PGT-A results and found that mosaic reporting did not meaningfully improve embryo selection or live birth prediction beyond standard criteria, suggesting that PGT-A’s main clinical value lies in identifying clearly aneuploid embryos.
A 2025 study suggests that most patients with recurrent pregnancy loss who transfer up to 3 euploid embryos go on to have a live birth, though data from later transfers are limited.
A 2025 study introduces the FORTUNE model, developed from over 10,000 PGT-A cycles, that uses age, ovarian reserve, partner age, and BMI to predict how many euploid embryos a patient is likely to produce by grouping patients into five prognosis categories.
A 2025 study found that while poor quality blastocysts are less likely to be euploid, some can still lead to healthy live births. Tested poor quality embryos had higher live birth rates and lower miscarriage rates than untested ones, especially when they developed by day 5 instead of day 6.
A 2025 meta-analysis combined 151 studies on interventions for advanced maternal age (>35) patients. It found no clear advantage to any specific stimulation protocol or FSH type, no benefit from routine ICSI, and decreased live birth with assisted hatching, while more research is needed on blastocyst versus cleavage-stage transfer and on PGT-A with modern methods.
This post traces the evolution of PGT-A testing in IVF, from early FISH and microarray methods to modern NGS and emerging technologies like nanopore sequencing, highlighting how each advancement improved accuracy, speed, and embryo assessment.
In a 2025 study, researchers estimated how many frozen eggs are needed, by age, to reliably yield three euploid blastocysts or achieve one, two or three live births, offering practical guidance for egg freezing patients.
A 2024 study explored the male and female factors that are associated with embryo euploid rates, finding that male characteristics had a minor influence.
Aneuploid embryos, with an abnormal number of chromosomes, are a major cause of miscarriages, often linked to maternal age and errors in meiosis. In this post, we’ll explore what chromosomes and aneuploidy are, how meiosis errors cause aneuploidy, and the factors contributing to these errors, including age, genetics and mitochondrial dysfunction.
A 2024 study compared successful and unsuccessful euploid transfers, finding that female age had no impact, while BMI, embryo quality and the type of FET used did.
In a 2024 study, researchers developed a model to help predict the number of mature eggs needed to obtain at least one euploid, based on age.
The ASRM has released their 2024 committee opinion on the use of PGT-A, covering the use of PGT-A for patients with a good prognosis, advanced age, donor eggs, recurrent pregnancy loss and more.
Researchers in a 2024 study found that patients that have 5 consecutive euploid transfers had a cumulative live birth rate of 98.1%, suggesting that most cases of implantation failure are due to the embryo, and that true unexplained RIF occurs in less than 2% of patients.
Researchers in a 2023 study compared PGT-A outcomes for patients with different diagnoses, including advanced maternal age (AMA), recurrent implantation failure (RIF), recurrent pregnancy loss (RPL) and severe male factor (SMF).
Researchers in a 2023 study found that patients with or without endometriosis have comparable live birth rates after transferring a euploid embryo, although patients may have been surgically treated (a limitation). Endometriosis patients are more likely to produce aneuploid embryos.
Researchers in a 2023 study combined the results of 74 studies to investigate what factors contribute to euploid live birth and miscarriage rates, identifying embryo quality, maternal age, specific diagnoses, repeat freeze/thaw, and other factors.
Researchers in a 2023 study evaluated factors affecting pregnancy outcomes after euploid transfer, and found that double euploid transfer, BMI, type of FET protocol, and the day of embryo biopsy all had an impact.
Small studies find that some chaotic embryos can be euploid after PGT-A rebiopsy, while a case report details a live birth after the transfer of a chaotic embryo.
