. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Study design, size, duration: Consecutive IVF patients <41 years of age were recruited at Nova Vita Clinic, Estonia, undergoing the antagonist stimu- lation protocol with rFSH administration. Ovarian puncture was performed for all patients after 36 hours of hCG stimulaton. rFSH dose >200 IU per one retrieved oocyte was considered as an indication for hyporesponse. Ten normo- and 9 hyporesponder patients were enrolled. Participants/materials, setting, methods: Cells from the follicular fluid devoid of the cumulus oocyte complex were collected by centrifugation. RNA-seq was performed on the pooled cells of all participants. The study groups were compared by differential gene expression analysis by DESeq2. Single-cell RNA-seq was performed for >6000 individual cells of 3 normores- ponder patients and cellular sub-populations were determined with Seurat package. CIBERTSORTx software was used to deconvolute the proportion of cell types from bulk RNA-seq data of all participants. Main results and the role of chance: Alterations in the gene expression of ovarian somatic cells have been previously attributed to female age. We dem- onstrate that 407 genes are differentially expressed (FDR<0.05) between normo- and hyporesponder IVF patients after age adjustment. These genes were enriched into pathways of extracellular matrix reorganization (31 genes, FDR<0.005), post-translational protein phosphorylation (16 genes, FDR<0.006) and regulation of insulin-like growth factor transport and uptake by insulin-like growth factor binding proteins (16 genes, FDR<0.019). In addition, the sequencing of > 24 000 individual cells from 3 normores- ponder patients revealed the somatic cell types of the preovulatory follicle in high resolution indicating the presence of immune cell populations (N ¼ 4), epithelial cells, theca, cumulus cells and mural granulosa cell sub-populations (N ¼ 7). Bioinformatic cell type deconvolution demonstrated significant differ- ences between proportions of distinct cell sub-populations between normo- and hyporesponder patients and that several differentially expressed genes between the study groups can be attributed to a specific mural granulosa sub- population. Limitations, reasons for caution: The number of study participants is small due to the high cost of the study methods. Wider implications of the findings: The study demonstrates that hypo- response to stimulation is associated with age-unrelated disturbances in gene expression of preovulatory somatic cells and that different somatic cell popu- lations may have important underlying functions in the ovarian etiologies of infertility. Trial registration number: not applicable Abstract citation ID: deac105.055 P-624 The type of vaccine received against SARS-CoV-2 does not affect ovarian function in an Assisted Reproduction cycle V. Vergara Bravo 1 , M. Cruz 1 , C. Gonza ´lez 2 , M.E. Ru  ız 1 , A. Requena 1 1 IVI Madrid, IVI RMA Global Headquarters Medical Affairs, Madrid, Spain 2 IVI Sevilla, IVI RMA Headquarters Medical Affairs, Sevilla, Spain Study question: Do the different types of vaccines against SARS-CoV-2 in- fluence the results of an Assisted Reproduction treatment? Summary answer: The type of vaccine administered against SARS-CoV-2 does not affect the results in women performing an Assisted Reproduction treatment. What is known already: Since the COVID-19 pandemic was declared, the search for vaccines has become the priority, so its development has repre- sented a step towards herd immunity in a short period of time. Despite this encouraging advance, vaccine hesitancy in reproductive-aged women has been heightened because of the spread of misinformation stating that COVID-19 vaccines will cause sterility. Due to the lack of information and the clinical relevance, the objective of this work was to evaluate the impact of the different types of vaccines on women’s fertility. Study design, size, duration: Retrospective and observational study during January-October 2021 in women vaccinated against SARS-CoV-2 and per- forming an Assisted Reproductive treatment in any of the 11 clinics belonging to the IVIRMA group in Spain. The Control group included patients perform- ing a treatment during the same study period but who had not yet been vaccinated. The study was approved by an Institutional Review Board (2109- MADR-084-AR) Participants/materials, setting, methods: All women, those who had re- ceived the complete vaccination schedule, regardless of the type of vaccine administered mRNA or viral vector, and women from the control group underwent the same ovarian stimulation protocol. The Assisted Reproduction treatment was performed with their own oocytes in all cases. Statistical analy- ses were performed using the Statistical Package for Social Sciences 19.0 (IBM Corporation, Armonk, NY, USA). Main results and the role of chance: We included 510 patients distributed as follows: 13.5% (n ¼ 69) received a viral vector vaccine either the adenovi- rus serotype 26 vector vaccine (Ad26.CoV2.S; Johnson & Johnson; n ¼ 31) or the chimpanzee adenovirus vector vaccine (ChAdOx; AstraZeneca; n ¼ 38). The remaining 86.5% (n ¼ 441) received an mRNA vaccine from either Pfizer-BioNTech (n ¼ 336) or Moderna (n ¼ 105). Sample size for control group was n ¼ 1190 Our results showed that women vaccinated with Johnson & Johnson have a higher average age (39.7 § 4.3) than the other groups, although no statisti- cal difference was observed (p ¼ 0.072); that is, AstraZeneca (36.8 § 1.7), Moderna (35.7 § 1.5), Pfizer (34.6 § 1.6) and the control group (37.8 § 2.7). This circumstance did not affect other parameters such as the days of stimulation (p ¼ 0.336) or the doses of FSH administered (p ¼ 0.392), where no statistical differences were recorded between the vaccinated and the con- trol group. Finally, the number of oocytes were as follows, Johnson & Johnson (9.2 § 2.6), AstraZeneca (7.7 § 1.2), Moderna (11.3 § 1.8), Pfizer (12.6 § 1.0), and the control group (10.2 § 1.5), p ¼ 0.06. Limitations, reasons for caution: This is an observational study, and thus possible confounders cannot be excluded entirely. More data are needed to draw firm conclusions, and it will be critical to increase the sample size to check if the results observed in this work remains in the general population Wider implications of the findings: This is the first study to assess whether the type of vaccine administered against SARS-CoV-2, mRNA, or vi- ral vector, affects ovarian function in ART. These early findings suggest no measurable detrimental on ovarian response regardless of vaccine received. Trial registration number: not applicable INVITED SESSION SESSION 48: EUROPEAN AND GLOBAL ART MONITORING Tuesday, 5 July 2022 Silver 11:45 - 12:45 Abstract citation ID: deac105.056 O-150 Assisted reproductive technology (ART) in Europe 2019 and development of a strategy of vigilance Preliminary results generated from European registers by the ESHRE EIM consortium C. Wyns 1 , Ch. De Geyter 2 , C. Calhaz-Jorge 3 , M.S. Kupka 4 , T. Motrenko 5 , J. Smeenk 6 , C. Bergh 7 , A. Tandler-Schneider 8 , I.A. Rugescu 9 , S. Vidakovic 10 , V. Goossens 11 1 Cliniques universitaires Saint-Luc, Universit  e Catholique de Louvain, Brussels, Belgium 2 Reproductive Medicine and Gynecological Endocrinology (RME), University Hospital, University of Basel, Switzerland 3 Faculdade de Medicina da Universidade de Lisboa, Portugal 4 Fertility Center - Gynaekologicum, Hamburg, Germany 5 Human Reproduction Center Budva, Montenegro 6 Elisabeth Twee Steden Ziekenhuis, Tilburg, the Netherlands 7 Dept of Obstetrics and Gynecology, Inst of Clinical Sciences, Go ¨teborg University, Go ¨teborg, Sweden 8 Fertility Center Berlin, Berlin, Germany 9 National Transplant Agency, Romania 10 Institute of Obstetrics and Gynecology, Clinical Center Serbia «GAK», Serbia i88 38th Hybrid Annual Meeting of the ESHRE, Milan — Italy, 3–6 July 2022 Downloaded from https://academic.oup.com/humrep/article/37/Supplement_1/deac105.056/6620042 by guest on 09 July 2022