Soy lecithin replaces egg yolk for cryopreservation of human sperm without adversely affecting postthaw motility, morphology, sperm DNA integrity, or sperm binding to hyaluronate

Semen specimens (one ejaculate from each of 20 consenting study participants) were subjected to routine semen analysis, an in vitro sperm binding assay (HBA), and a sperm chromatin dispersion assay (HaloSperm), both before and after cryopreservation using cryoprotectant media supplemented with either egg yolk or soy lecithin. Comparing the equivalency of the two phospholipid cryopreservation supplements with regard to postthaw functional parameters demonstrated that there were no statistically significant differences between the two supplements for [1] recovery of motile sperm, [2] maintenance of sperm cell morphology, [3] maintenance of the ability of sperm to bind to hyaluronate in vitro, or [4] maintenance of sperm DNA integrity.

Large-volume vitrification of human biopsied and non-biopsied blastocysts: a simple, robust technique for cryopreservation

PURPOSE

To evaluate the transition from a proven slow-cooling cryopreservation method to a commercial large-volume vitrification system for human blastocysts.

METHODS

Retrospective analysis of de-identified laboratory and clinical data from January 2012 to present date for all frozen embryo replacement (FET) cycles was undertaken. Cryopreservation of trophectoderm-biopsied or non-biopsied blastocysts utilized during this time period was logged as either slow-cooling, small-volume vitrification, or large-volume vitrification. Blastocyst survival post-warm or post-thaw, clinical pregnancy following FET, and implantation rates were identified for each respective cryopreservation method.

RESULTS

Embryo survival was highest for large-volume vitrification compared to micro-volume vitrification and slow-cooling; 187/193 (96.9 %), 27/32 (84.4 %), and 244/272 (89.7 %), respectively. Survival of biopsied and non-biopsied blastocysts vitrified using the large-volume system was 105/109 (96.3 %) and 82/84 (97.6 %), respectively. Survival for micro-volume biopsied and non-biopsied blastocysts was 16/30 (83.3 %) and 2/2 (100.0 %) respectively. Slow-cooling post-thaw embryo survival was 272/244 (89.7 %). Clinical pregnancy and implantation rates outcomes for non-biopsied embryos were similar between large-volume and slow-cooling cryopreservation methods, 18/39 (46.2 %) clinical pregnancy and 24/82 (29.3 %) implantation/embryo, and 52/116 (44.8 %) clinical pregnancy and 67/244 (27.5 %) implantation/embryo, respectively. Comparing outcomes for biopsied embryos, clinical pregnancy and implantation rates were 39/67 (58.2 %) clinical pregnancy and 50/105 (47.6 %) implantation/embryo and 4/16 (25 %) clinical pregnancy and 6/25 (24.0 %) implantation/embryo, respectively.

CONCLUSIONS

The LifeGlobal large-volume vitrification system proved to be very reliable, simple to learn and implement in the laboratory. Clinically large-volume vitrification was as, or more effective compared to slow-cooling cryopreservation in terms of recovery of viable embryos in this laboratory.

Live birth after anonymous donation of twice-cryopreserved embryos that had been stored in liquid nitrogen for a cumulative storage time of approximately 13.5 years

OBJECTIVE

To report a live birth after transfer of anonymously donated, twice-cryopreserved embryos that had been stored in liquid nitrogen for approximately 13.5 years.

DESIGN

Case report.

SETTING

A private assisted reproduction center.

PATIENT(S)

A 44-year-old recipient of donated cryopreserved embryos.

INTERVENTION(S)

Anonymous donation of cryopreserved blastocysts for procreation.

MAIN OUTCOME MEASURE(S)

Live birth after thawing and replacement of re-cryopreserved blastocysts.

RESULT(S)

Fourteen pronuclear-stage embryos and four cleavage-stage embryos were cryopreserved during a primary IVF cycle. In two separate cycles, one cycle for the primary patient and a subsequent cycle for the first embryo donor recipient, the 18 embryos were thawed and grown to the blastocyst stage for transfer. Supernumerary blastocysts (n = 5) not replaced at either of these two thaw cycles were re-cryopreserved and subsequently donated to another embryo donor recipient. Five blastocysts survived the thaw and three were transferred, resulting in a live birth. The embryos were cryopreserved for a cumulative storage time of approximately 4,909 days (13.4 years).

CONCLUSION(S)

The longevity (viability) of cryopreserved embryos maintained in liquid nitrogen remains to be determined; cryopreserved embryo donation for procreation should not be overlooked, regardless of the length of time that embryos remain in cryostorage.