P-925: The effect of pre-implantation genetic diagnosis on day 5 vs. day 6 embryo transfer outcomes

Abstract

To determine the effect of Pre-implantaion Genetic Diagnosis (PGD) on pregnancy rate as it relates to day 5 and day 6 blastocyst transfer outcomes. A retrospective clinical analysis of patients undergoing PGD with subsequent blastocyst transfer on day 5 or day 6 after oocyte retrieval. 199 completed cycles of patients undergoing in vitro fertilization - embryo transfer (IVF-ET) with controlled ovarian hyperstimulation (COH) were reviewed. 78 cycles of women undergoing in-vitro fertilization-embryo transfer with preimplantation genetic diagnosis from January 1, 2005 to January 1, 2006 were analyzed for pregnancy rates. An additional 121 cycles of IVF-ET without PGD and subsequent day 5 or day 6 blastocyst transfers were used as controls. Pregnancy was defined as the presence of positive serum beta hCG two weeks after embryo transfer. The difference in mean age between the two groups was analyzed using the unpaired student t test. Patients were further stratified according to day of blastocyst transfer. Fisher’s exact test was used to analyze data and determine if a significant difference exists. Mean age of patients with PGD and without PGD : 37.53 vs 36.62 respectively; p = 0.2649 PGD embyos: PR 62% vs 64% for D5 and D6 respectively; p = 1.00 Non-PGD embryos: PR 73% vs 62% for D5 and D6 respectively; p = .2420 Day 5 embryos: PR 62% vs 73% for PGD vs non-PGD respectively; p = .2813 Day 6 embryos: PR 64% vs 62% for PGD vs non-PGD respectively; p = 1.00. Whereas the advantages of preimplantation genetic diagnosis are sometimes clear, the effects on pregnancy rate based on day of transfer are not so obvious. Although not statistically significant, there is a trend towards a poorer pregnancy rate with embryos undergoing PGD transferred on day 5 compared to day 5 embryos that had not undergone PGD. Furthermore, there does not appear to be an additional benefit by transferring PGD-embryos on day 6 rather than day 5. Therefore, his study has illuminated one of the drawbacks of patients undergoing PGD without a true clinical indication.