The effect of the day of cryopreservation on FET success rates in PGS and non-PGS blastocysts

Abstract

53.8% vs. 22.5%; p¼ .027). In 19 cases, one or more contractions of the blastocyst were observed but no relation with implantation was confirmed.CONCLUSIONS: The analysis of warmed blastocysts by time lapse imaging is providing new promising markers for blastocyst implantation potential and represents a novel alternative to morphological evaluation, establishing objective quantitative values linked with clinical outcome. However, further studies are required to validate the predictive power of this technology.OBJECTIVE: This study aimed to identify potential lipid biomarkers related to the embryo vitrification, since this procedure is extremely important for assisted reproduction and may affect the development and the lipid profile of embryos.DESIGN: Prospective study. MATERIALS AND METHODS: Mice females C57BL/6J were superovulated, the embryos were collected after 60 hours in 8-cell stage and were divided into two groups: the control group, in wich embryos were cultured in 5% CO2 incubator until the blastocyst stage and evaluated based on their development time, and the experimental group, composed of vitrified embryos, that were thawed after 5 days, cultured in 5% CO2 until the blastocyst stage and also evaluated based on their development time. The lipids were extracted using the Bligh & Dyer method and were analyzed by Matrix-assisted laser desorption/ionization (MALDI-TOF/MS). Statistical analysis was performed using Principal Component Analysis (PCA) and partial least squares -discriminant analysis (PLS-DA), and the 15 ions corresponding to the potential lipid biomarkers were identified by the variable importance in projection (VIP).RESULTS: There was a lower rate of vitrified blastocyst group of 75.60% against 94.82% in the control group and variation in the rate at 24.40% of degenerated embryos vitrified group and 5.18% in the control group and rate variation in the degenerate embryos vitrified group of 24.40% and 5.18% in the control group. The PCA demonstrated that the principal component five better indicates the variance between the groups, presenting a prediction model with 81% of accuracy. The experimental group presented ganglioside, anthocyanins, phosphatidylglycerol, phosphatidylcholine, phosphatidylinositol as higher represented lipids and the experimental group presented flavonoids, phosphatidylserine and anthocyanins hyper-represented.CONCLUSIONS: There was a significant difference between the development rate after vitrification and the lipid profile differs significantly between embryos in the blastocyst stage and embryos subjected to cryopreservation. The lipids found in this study are related to good embryo quality in the control group and may present a broadly correlation with altered metabolism in the experimental group, indicating that despite the vitrification is essential, this is a procedure that affects the lipids embryo quality. This lipids are potential biomarkers since they may help in the development of procedures that may improve vitrification and reduce embryos damage.