Experts suggest the routine use of PGS to improve the results of IVF
Although preimplantation genetic screening (PGS) remains optional except where clinically indicated, experts are pondering whether its use should be expanded to a universal embryo selection method in all assisted reproduction techniques (ART) treatments requiring in vitro fertilisation (IVF).
This method is currently restricted to certain indications such as advanced maternal age (≥ 38 years), implantation failure (≥ 3 embryo transfers without pregnancy or ≥ 5 embryos transferred), recurrent miscarriage (≥ 2 miscarriages of unknown cause) or diagnosis of a severe male fertility problem. However, multiple studies have demonstrated the effectiveness of PGS in improving the success of IVF, as its use increases rates of pregnancy and implantation after embryo transfer both in young women with good prognosis and patients of advanced maternal age. In addition, it allows the selective transfer of a single embryo with no chromosomal abnormalities, and reduces the rate of miscarriage, the number of multiple pregnancies, and the time required to achieve the goal of IVF, that is to say, the birth of a healthy child.
A team of experts in embryology and in the clinical field recently held a meeting in our centre to discuss and update the protocols to be followed in PGS in order to optimise its results. This technique is now far more accurate and effective in detecting and preventing the transfer of embryos with genetic defects, thanks to, inter alia, improvements made to IVF labs such as the addition of time-lapse incubators, which allow uninterrupted culture of embryos, embryo biopsy at the blastocyst stage, complete chromosome analysis, and deferred embryo transfer. However, experts suggest that for patients to benefit from all these advances and in order to maximise the performance of PGS, it is essential that it be performed in centres with the appropriate equipment and technology, and with the necessary human and material resources.
On the other hand, it has been established that, if supported by a good explanation that justifies its use, 74% of the patients would agree to undergo PGS, and that its cost would influence the decision only to a negligible extent.
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