P-247 Total Fertilization Failure after conventional IVF: it is not the end of the story

Abstract Study question Could Rescue IntraCytoplasmatic Sperm Injection (R-ICSI) coupled with frozen transfers be an effective treatment for Total Fertilization Failure (TFF) after conventional InVitro (c-IVF) cycles? Summary answer Applying R-ICSI TFF of c-IVF, a blastulation rate 28% could obtained, allowing the cycle rescue in consistent proportion couples. What is known already Conventional IVF to date most indicated technique infertile couples absence male factor. However, incidence following presence normozoospermic samples, ranges from 5 20%. leaves experts limited alternatives, which include cancelling subsequent indication proceed ICSI next or attempting current cycle. embryo transfer may overcome technical and biological issues associated fresh R-ICSI, possibly representing efficient procedure experiencing c-IVF. design, size, duration Our retrospective study included 33 who underwent assisted reproduction techniques (ART) at Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico Milan October 2021 December 2022 that experienced regardless number oocytes retrieved. Overall, was reported 7% c-IVF cycles (33/439). An factor infertility exclusion criterium. World Health Organization (WHO) reference values human semen characteristics have been adopted. Participants/materials, setting, methods failure considered terms two pronuclei second polar body. Out 158 unfertilized oocytes, 128 MII were microinjected same consists performing 22-24 hours insemination unsuccessful using sample maintained room temperature overnight. Fertilized cultured blastocyst stage according our standard protocol. Main results role chance The fertilization 42% (95%CI: 34-51%). still observed 9 patients (27%, 95%CI: 13-46%) median value 2 [2-5] available insemination. In 24 obtained least one zygote, 16-42%). A total 15 blastocysts cryopreserved 10 on day 6 R-ICSI. Of these patients, undergone frozen/thawed single transfer, success (ongoing pregnancy) 50% 12-88%). Limitations, reasons caution One limitations small since this emergency procedure. ongoing. Women not subjected inclusion criteria, thus attributed several factors different quality. Wider implications findings This turns out important light interesting implantation obtained. With advantage reducing both costs psychological burden couple, can proposed as strategy cases confidently increase Trial registration applicable