No abstract

An increase in imprinting disorders in children conceived though assisted reproductive technologies (ARTs) has been the subject of several reports. The transmission of imprinting errors from the sperm of infertile fathers is believed to be a possible reason for the increased occurrence of these disorders. However, whether the imprinting alterations in sperm affect ART outcomes and the imprinting of offspring is unclear. In the current study, we analyzed the methylation of H19, SNRPN and KCNQ1OT1 by pyrosequencing sperm samples from 97 infertile patients and 31 proven fertile males as well as cord blood samples from 13 infantswho were conceived by infertile parents through intracytoplasmic sperm injection (ICSI) and 30 healthy newborns who were conceived naturally. After four cases were excluded owing to the lack of a sequencing signal, the infertile patients were subgrouped into normal (69 cases) and abnormal (24 cases) imprinting groups according to the reference range set by the control group. Between the groups, there were no significant differences in ART outcomes. Significantly different levels of methylation were detected in H19, but none of the imprinted genes were determined to be outside of the methylation reference range set by the values derived from the naturally conceived controls. Three CpG loci were found to be significantly hypomethylated in the maternally imprinted gene KCNQ1OT1 in two patients from the abnormal imprinting group, none of which were caused by sperm imprinting errors. In addition, the paternal H19 gene exhibited discrepant methylation patterns between the sperm controls and the cord blood controls. Our data suggest that increased imprinting errors in the sperm of infertile patients do not have an obvious influence on ART outcomes or the imprinting of offspring.

Study question Is ERA testing different between RIF patients with control group? Summary answer In RIF patients, there were more chances of non-receptive endometrium. ERA testing may be helpful for the patients with repeated IVF failure. What is known already: The endometrium receptivity analysis testing might have the ability to detect the implantation window. In repeat implantation failure patients, detecting of precisely implantation window may have some benefits. Study design, size, duration This was a single-center retrospective observational study. Two hundred and forty-nine patients who underwent ERA testing following frozen-thawed embryo transfer in our center were including in this study between January 2019 and May 2020. Participants/materials, setting, methods 181 patients having unexplained repeated IVF failure (RIF group, at least tow implantation failure) and 68 patients having no experience with embryo transfer (Control group) who underwent ERA testing were including in this study. Both of Patients having a receptive (R) ERA and having a non-receptive (NR) ERA underwent a personalized embryo transfer (pET) on ERA. ERA results and clinical outcomes compared between RIF group and control group were analyzed by Chi-square test. Main results and the role of chance The proportion of R/NR results were 33:35 for the RIF group and 118:63 for the Control group, demonstrating the displacement of the window of implantation in patients with RIF. Our results revealed an endometrial factor in 51% RIF patients, which was significantly greater than the Control group 34.8% (P = 0.02). Among the patients with NR ERA result, there are not significantly difference in clinical pregnancy rate in the RIF group compared with control group (57.1%. vs. 61.9%). The clinical pregnancy rate of the patients with receptive ERA result also is comparable in both group (70.3% vs. 66.7%). Limitations, reasons for caution This is a retrospective, single center study with limited case number. There were may some bias with ERA testing errors. Wider implications of the findings: In RIF patients, there were more chances of non-receptive endometrium. ERA testing may be helpful for the patients with repeated IVF failure. Larger randomized studies are required to validate these results. Trial registration number 18MMHISO70e

The purpose of this study is to assess the impact of different temperatures and equilibrium times on the clinical outcomes of FET cycles during the thawing procedure and to select a better thawing method to improve clinical outcomes. Methods

Purpose The purpose of this study is to assess the impact of different temperatures and equilibrium times on the clinical outcomes of FET cycles during the thawing procedure and to select a better thawing method to improve clinical outcomes. Methods This retrospective study included 1,734 FET cycles from January 1, 2020, to January 30, 2022. Embryos vitrified using a Kitazato Vitrification Kit were thawed at 37°C in all steps (the case group, denoted the “all-37°C” group) or at 37°C and then at room temperature (RT; the control group, denoted the “37℃-RT” group), according to the kit instructions. The groups were matched 1:1 to avoid confounding. Results After case-control matching, 366 all-37°C cycles and 366 37℃-RT cycles were included. The baseline characteristics were similar (all P > 0.05) between the two groups after matching. FET of the all-37°C group yielded a higher clinical pregnancy rate (CPR; P = 0.009) and implantation rate (IR; P = 0.019) than FET of the 37℃-RT group. For blastocyst transfers, the CPR (P = 0.019) and IR (P = 0.025) were significantly higher in the all-37°C group than in the 37℃-RT group. For cleavage embryo transfers, the CPR and IR were non-significantly higher in the all-37°C group than in the 37℃-RT group (P > 0.05). Conclusions Thawing vitrified embryos at 37°C in all steps during FET cycles can enhance CPR and IR. Well-designed prospective studies are warranted to further evaluate the efficacy and safety of the all-37°C thawing method.