Here is the linky to that study
Title:
First PGT-A using human in vivo blastocysts recovered by uterine lavage: comparison with matched IVF embryo controls†
https://academic.oup.com/humrep/advance-article/doi/10.1093/humrep/dez242/5678546?searchresult=1
Scientists have already retrieved unfertilized ova in this fashion. They could do their in vitro genetic testing that way, after fertilization, and have.
They’ve been doing it for at least 35 years, in fact. Here’s a study from 1985. https://www.ncbi.nlm.nih.gov/pubmed/4037016
What is the advantage to retrieving embryos rather than ova? Probably life span. An ovum lives 24 hours, an embryo (developing human) potentially 100 years, unless you kill it in the name of science.
Even for people who don’t value the life of an embryo in the least, you would think more of them would have ethical qualms about exploiting poor and uneducated women, and putting them at risk. Ovarian hyperstimulation is not an entirely benign procedure.