This is one of a series of news items from abstracts of studies presented at the Annual Meeting of the American Society for Reproductive Medicine as complied by Dr. David Meldrum, Scientific Director of Reproductive Partners. We appreciate the enormous amount of work it takes to compile and comment on these abstracts.
In a study reported at ASRM the two best embryos were selected for transfer and at random, one had a biopsy and the other did not. DNA fingerprinting was done to confirm which embryos implanted. Day 3 biopsy decreased implantation from 53 to 31%, whereas the implantation rates for day 5 were similar at 52 and 54%. This study confirmed that day 3 biopsy adversely affects the ability of the embryo to implant. The actual reduction would require a much larger sample. Day 5 showed no reduction but with a sample size of 71, a small effect could have been missed. Together with day 3 errors due to mosaicism and allele drop-out, these data indicate that day 5 biopsy should be the procedure of choice.
At RPMG we perform day 5 biopsies for preimplantation generic screening (PGS) for chromosomes and poreimplantation genetic diagnosis (PGD) for single gene defects,