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Reopening fertility care services across the world in the midst of a pandemic brings with it numerous concerns that need immediate addressing, such as the impact of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on the male and female reproductive cells and the plausible risk of cross-contamination and transmission. Due to the novelty of the disease the literature contains few reports confirming an association of SARS-CoV-2 with reproductive tissues, gametes and embryos. Cryobanking, an essential service in fertility preservation, carries the risk of cross-contamination through cryogenic medium and thus calls for risk-mitigation strategies. This review aims to address the available literature on the presence of SARS-CoV-2 on tissues, gametes and embryos, with special reference to the possible sources of cross-contamination through liquid nitrogen. Strategies for risk mitigation have been extrapolated from reports dealing with other viruses to the current global crisis, for safety in fertility treatment services in general, and specifically for oncofertility.

This study investigated if in vitro maturation (IVM) before or after vitrification would be more successful for prepubertal oocytes. To mimic prepubertal conditions in an experimental setup, oocytes were collected from healthy 14, 21 and 28day old Swiss albino mice. The germinal vesicle (GV) stage oocytes and in vitro matured MII oocytes were subjected to vitrification-warming. Both structural (meiotic spindle morphology, mitochondrial integrity, cortical granules) and functional (sperm zona binding, fertilization) characteristics were assessed in oocytes after warming. This study demonstrated that IVM was more detrimental to prepubertal oocytes than to young adults. Further, vitrification of the IVM oocytes resulted in an increase in the number of abnormal meiotic spindles, a change in the cortical distribution pattern, a reduction in sperm zona binding and the fertilization rate. Importantly, oocyte integrity was better when prepubertal oocytes were vitrified before, rather than after, IVM. The above observations support GV stage vitrification for prepubertal oocytes requiring fertility preservation. Understanding the mechanisms behind the differing outcomes for oocytes from immature females will help in refining current protocol, thereby retaining the oocytes' maximum structural and functional integrity Further investigation is necessary to determine whether human prepubertal oocytes also behave in a similar way. It is to be noted here, with great emphasis, that a major limitation of this study is that the oocytes’ abilities were tested only until fertilisation, as a consequence of which the study cannot reveal the developmental potentials of the embryos beyond fertilisation.