DNA methylation and mRNA expression of imprinted genes in blastocysts derived from an improved in vitro maturation method for oocytes from small antral follicles in polycystic ovary syndrome patients

AbstractSTUDY QUESTIONDoes imprinted DNA methylation or imprinted gene expression differ between human blastocysts from conventional ovarian stimulation (COS) and an optimized two-step IVM method (CAPA-IVM) in age-matched polycystic ovary syndrome (PCOS) patients?SUMMARY ANSWERNo significant differences in imprinted DNA methylation and gene expression were detected between COS and CAPA-IVM blastocysts.WHAT IS KNOWN ALREADYAnimal models have revealed alterations in DNA methylation maintenance at imprinted germline differentially methylated regions (gDMRs) after use of ARTs. This effect increases as more ART interventions are applied to oocytes or embryos. IVM is a minimal-stimulation ART with reduced hormone-related side effects and risks for patients. CAPA-IVM is an improved IVM system that includes a pre-maturation step (CAPA), followed by an IVM step, both in the presence of physiological compounds that promote oocyte developmental capacity.STUDY DESIGN, SIZE, DURATIONFor DNA methylation analysis 20 CAPA-IVM blastocysts were compared to 12 COS blastocysts. For RNA-Seq analysis a separate set of 15 CAPA-IVM blastocysts were compared to 5 COS blastocysts.PARTICIPANTS/MATERIALS, SETTING, METHODSCOS embryos originated from 12 patients with PCOS (according to Rotterdam criteria) who underwent conventional ovarian stimulation. For CAPA-IVM 23 women were treated for 3 –5 days with highly purified hMG (HP-hMG) and no hCG trigger was given before oocyte retrieval. Oocytes were fi...
Source: Human Reproduction - Category: Reproduction Medicine Source Type: research