Research On The Effects Of Endometriosis On Oocyte And Embryo Quality In Patients With Infertility:

Part Ⅰ Effects of endometriosis and its stage on oocyte and embryo quality in infertile patients undergoing in vitro fertilization-embryo transfer:a retrospective studyObject:Endometriosis is one of the indications for in vitro fertilization-embryo transfer（IVF-ET）.However,the effects of endometriosis on ovarian response,oocyte and embryo quality in patients receiving IVF-ET remain controversial.The objective of this retrospective study was to analyze the effects of endometriosis and its stage on oocyte and embryo quality in infertile patients undergoing IVF-ET.Methods:Infertile patients with endometriosis or obstruction of fallopian tube who underwent IVF-ET treatment in our hospital from July 2015 to December 2020 were included in this study.In the endometriosis group,patients were further divided into two subgroups based on their stages of endometriosis lesions,namely stage Ⅰ-Ⅱ group and stage Ⅲ-Ⅳ group.Subsequently,statistical analysis was used to identify the differences in the number of retrieved oocytes,the number of mature oocytes（MII oocytes）,fertilization rates,percentages of cleavage-stage embryos with good quality,the number of cleavages,the number of blastocysts and blastocyst formation rates in different groups.Meanwhile,the generalized linear model was used to eliminate the interference of confounding factors and adjust the results.Results:A total of 1,312 IVF cycles were included in this study.Patients with endometriosis had higher level of baseline FSH and higher consumption of gonadotropins than that in the control group（both P<0.001）,in addition,the higher the endometriosis stage,the higher the level of FSH and the greater the usage of gonadotropins.The endometriosis group had a lower percentage of good cleavage-stage embryos[the mean was 10%（0%,16.7%）and 12.2%（0%,20%）,respectively]and fertilization rates[the mean was 75.7%（60%,100%）and 79.5%（66.7%,100%）,respectively]than those in the control group（adjusted P=0.038 and 0.008,respectively）.The number of oocytes retrieved,MII oocytes,cleavages,blastocysts,and blastocyst formation rates were comparable between two groups.Stratification analysis showed that patients with stage Ⅲ-Ⅳ endometriosis had fewer oocytes retrieved than those with stage Ⅰ-Ⅱ endometriosis[median 6（4,9）vs.median 8（5,11）,adjusted P=0.012)and marginally fewer than the control group（adjusted P=0.051）.The stage Ⅰ-Ⅱ group had the lowest percentage of good cleavage-stage embryos[mean 9.2%（0%,16.7%）],which was significantly lower than that of the control group（adjusted P=0.043）.Conclusions:Our results suggest that endometriosis and its stage affect embryo quality,oocyte fertilization ability,and ovarian response.Part Ⅱ Sequencing and bioinformatic analysis of circular RNAs in cumulus cells from patients with endometriosis associated infertilityObject:Endometriosis is thought to have detrimental effects on oocyte quality,and different phenotypes of endometriosis,for example,ovarian endometriosis（OEM）and peritoneal endometriosis（PEM）,may have different effects on female fertility.Therefore,this study was aimed at investigating the circular RNAs（circRNAs）expression profiles of cumulus cells in patients with OEM infertility,PEM infertility and tubal factor infertility（TFI）,as well as to explore the potential mechanisms by which different phenotypes of endometriosis impair oocytes by using bioinformatic analysis methods.Methods:circRNAs expression profiles of cumulus cells in patients with OEM（n=3）,PEM（n=3）and TFI（n=3）were verified by using high-throughput sequencing techniques,meanwhile,the differences between the groups were analyzed.Subsequently,the common and unique circRNAs in the OEM and PEM groups were identified by taking intersections.The relative expression levels of seven selected differentially expressed circRNAs were validated by using quantitative real-time polymerase chain reaction（qRT-PCR）（sample size n=30）.circRNA-miRNA-mRNA network（competitive endogenous RNA network）was constructed according to the validated circRNAs,in order to find the target genes of circRNAs.Finally,functional analysis,including Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analysis,was performed to annotate the function of circRNA-targeted genes.Results:A total of 11,833 circRNAs were identified in nine samples.The numbers of differentially expressed circRNAs between the groups of OEM and TFI,PEM and TFI as well as OEM and PEM were 130,71,and 191,respectively.After taking intersections,11 circRNAs were considered common circRNAs in the OEM and PEM groups;39 circRNAs in the OEM group and 17 circRNAs in the PEM group were identified as unique key circRNAs.During qRT-PCR validation,hsa_circ₀004872 was found to be significantly upregulated in the PEM group compared to that in the OEM and TFI groups.Functional analysis of circRNA-targeted genes revealed that apoptosis,PI3KAKT and p53 signaling pathways were enriched in the PEM-TFI comparison groups,whereas the functions of target genes involved in the JAK-STAT and TGF-β signaling pathways were enriched in the PEM-OEM comparison groups.Conclusions:Our findings confirmed differences in circRNAs expression profiles of cumulus cells between patients with OEM and PEM infertility,and we also identified the key circRNA（hsa_circ₀004872）and important signaling pathways in the process of PEM lesions impairs oocyte quality and capacity.