Although current techniques allow the selection of embryos with a correct chromosomal complement (known as euploid embryos), a new study conducted by the IVF-Life Group has shown that maternal age continues to play a decisive role in reproductive success. The research, led by embryologist María Velasco, analyzed the results of 270 euploid embryo transfers from patients using their own eggs, classifying them by age range. The results reveal that, although the transfer of genetically optimal embryos increases the chances of pregnancy in older women, it does not achieve the same outcomes as in younger patients.
The study divided patients into four age groups: under 34 years, 34–39, 40–41, and 42 years or older. All of them received a euploid embryo selected through preimplantation genetic testing for aneuploidy (PGT-A), a technique that allows the chromosomal number to be analyzed before implantation.
The data showed that pregnancy and gestation rates decrease with age, even when the embryo is chromosomally normal. In women under 34, the clinical pregnancy rate reached 87.5%, while it was 77.9% among those aged 34 to 39. In patients aged 40 to 41, the rate dropped to 61.4%, and to 50.7% in those aged 42 or older. A similar trend was observed in the ongoing pregnancy rate (pregnancies that progress normally), which fell from 79.2% in the youngest group to 45.1% in the oldest.

“These results confirm that although selecting euploid embryos significantly improves outcomes, maternal age remains a crucial factor affecting success rates. Genetics is a powerful tool, but it cannot fully compensate for the effects of age on reproduction,” explains María Velasco.
The study also points out that the lower pregnancy rates observed from age 42 onwards could be due not only to reduced embryo quality but also to a smaller number of embryos available for selection and possible endometrial or uterine abnormalities. Moreover, cellular aging and hormonal changes may influence uterine receptivity, which could explain why even chromosomally normal embryos do not always implant successfully.
The study will be presented at the ASEBIR Congress 2025 and reinforces the idea that, although science continues to advance, biology still sets certain limits that must be considered in clinical practice.