P-173 Neuregulin 1 supplementation and sequential stimulation improve post-IVM embryo production

Abstract Study question Can supplementation with neuregulin 1 during a pre-IVM culture step followed by sequential stimulation FSH and amphiregulin improve IVM outcomes? Summary answer Supplementation improves post-IVM bovine embryo production What is known already Evidence that gradual activation of the maturation cascade favours nuclear-cytoplasmic synchrony cumulus-oocyte communication has motivated investigation steps. In vivo, complex (COC) first exposed to increased levels, after which final triggered EGF-like factors secreted granulosa cells. We have demonstrated medium (NRG1), modulatory factor, oocyte developmental competence. Herein, we utilized model assess impacts NRG1 exposure (AREG) on post-IVF development design, size, duration Bovine COCs were subjected (group NS) or without (groups D S). Subsequently, direct D) AREG S NS). Post-IVF total high quality (expanded hatched) blastocysts was compared between groups ANOVA Fisher Protected test (n = 3 replicates, each 20-25 oocytes per treatment-group) Participants/materials, setting, methods Germinal stage vesicle aspirated from 2-8mm follicles abattoir ovaries, pooled in for 9h “Follicular System” (FS)-preIVM medium, 1ng/mL NRG1, FS-IVM 24h. IVM, 6h and, subsequently, 18h complete (AREG 100ng/mL) Main results role chance combined as assessed percentage pre-IVM/IVM generating blastocysts. Total blastocyst rates 34.34 ± 1.66%, 40.26 1.94% 45.94 3.04% D, NS, respectively (P 0.032). Rates 30.53 1.47%, 29.71 2.36% 38.56 1.91%, 0.036) Limitations, reasons caution Our study intrinsic limitations use an animal model. Treatment effects may vary different biological activities associated batches suppliers Wider implications findings contribute better understanding mechanisms regulating competence constitute novel parameters improvement efficacy. Therefore, our data infertility treatment strategies reduced hormonal cost patient discomfort Trial registration number Not applicable