Why PGT-A, most likely, improves IVF success.

Preimplantation genetic testing for aneuploidies (PGT-A), with its vocal advocates and opponents, is at the epicentre of a perpetual, often heated, debate. The main issues include the following. First, how do we interpret the existing evidence-base? Around 100 retrospective and single-centre studies, two non-selection trials and at least two meta-analyses point to its efficacy in improving live birth rates, although randomized controlled trials are more mixed. Second, what should be done in relation to euploid/aneuploid mosaicism? Recent data suggest that low-level mosaic pregnancies can proceed uneventfully to term, so intelligent interpretation of the diagnostic data is appropriate. Third, what is the stance of the Human Fertilisation and Embryology Authority? The 'traffic light' system is much debated and is perhaps best described as well-intentioned, but misguided in places. Fourth, what is the motivation of people who maintain their point of view despite the evidence? Sadly, the presentation of new empirical evidence polarizes, rather than reconciles, opinion. Too many have made a career out of either promoting or denigrating PGT-A for them to back down easily. Finally, how can we find common ground and move forward? All patients should be counselled in a non-directive manner on whether to embark on PGT-A, summarizing for them the whole evidence base so they can make up their own mind.