Oocyte and embryo vitrification in the IVF laboratory: a comprehensive review

Vitrification is an excellent tool in the IVF laboratory, enabling options and offering flexibility in assisted reproduction. The technology of cryopreservation has been underway since the early 20th century. The advent of vitrification has advanced the expectations in routine clinical practice in the IVF laboratory presenting impressive results both in post-thaw survival, and in clinical pregnancy rates, as well as significantly enhancing clinical results on preimplantation genetic diagnosis (PGD). Contradicting opinions have been published recently on the limitations and potential that vitrification has in the laboratory, as well as on the optimal approach to employ vitrification in IVF. This review aims to present a comprehensive analysis of the practical aspects of vitrification including concerns and options regarding its use on oocytes and embryos while comparing it with the traditional "slow-freezing" cryopreservation technique.