Efficiency of aseptic open vitrification and hermetical cryostorage of human oocytes

Abstract

The present study reports, as far as is known for the first time, the safety of UV sterilization of liquid nitrogen and hermetical cryostorage of human oocytes by comparing the efficiency of fresh and vitrified sibling oocytes of infertile patients. A prospective randomized study on sibling oocytes of 31 patients was carried out. Metaphase-II oocytes were randomized for intracytoplasmic sperm injection and the supernumerary sibling oocytes were vitrified using a novel Cryotop aseptic procedure (UV liquid nitrogen sterilization and hermetical cryostorage). After unsuccessful attempts with fresh oocytes, vitrified sibling oocytes were injected. Mean outcome measures observed were fertilization, cleavage and top-quality embryo rates. No significant differences were observed between the fresh and vitrified-warmed sibling oocytes: oocyte fertilization was 88.3% versus 84.9%; cleavage 72.6% versus 71.0%; top-quality embryos 33.8% versus 26.3% and mean number of transferred embryos 2.6 ± 0.1 versus 2.5 ± 0.1, respectively. Clinical pregnancy rate per cycle with vitrified-warmed oocytes was 35.5% (implantation rate 17.1%) and seven healthy babies were born. This study demonstrated that UV liquid nitrogen sterilization and hermetical cryostorage does not adversely affect the developmental competence of vitrified oocytes, allowing safe aseptic open vitrification applicable under strict directives on tissue manipulation.

Adolescent and Young Adult Oncology, Version 2.2018, NCCN Clinical Practice Guidelines in Oncology

“…52,101 Evidence from randomized trials [114][115][116][117] and a meta-analysis 118 suggest that IVF with cryopreserved oocytes results in fertilization and pregnancy rates similar to that of fresh oocytes. Oocyte cryopreservation is no longer considered investigational according to guidelines from the American Society of Reproductive Medicine.…”

Experiences in fertility preservation: lessons learned to ensure that fertility and reproductive autonomy remain options for cancer survivors

“…Recent advances in technology have demonstrated success rates comparable to fresh IVF [5,21,32]. In addition, laboratory evaluation of oocytes retrieved in the setting of cancer appears comparable to those harvested for non-malignant indications [26,40]. OC offers reproductive-age patients several advantages including: eliminating the need for donor sperm, Capsule While undergoing cancer treatment, females considering fertility preservation can often complete these processes concomitantly.…”

Blastocyst transfer after aseptic vitrification of zygotes: an approach to overcome an impaired uterine environment

“…For this reason, great effort is taken to at least minimize the risk of contamination for the embryos during the vitrification process and when they are directly plunged into LN 2 . Various methods for sterilizing LN 2 , including ceramic filters (Cobo et al, 2011) or UV-light simultaneously with hermetical cryostorage (Parmegiani et al, 2010(Parmegiani et al, , 2011, are under development and are both technically complex and expensive.…”