Table 3.
Functional survival of fresh and vitrified mouse oocytes and 2-cell embryos
| Vitrification sol’n | # eggs/2-cell embryos (# runs) | N (%) Morpholog. Normal | N (%) 2-cell | N (%) Expanded Blastocyst |
|---|---|---|---|---|
| A. Oocytesa | ||||
| None (Control) | 40 (8) | 40 (100) | 38 (95 ± 3.3) | 32 (80 ± 3.8) |
| 0.33–4b | 40 (8) | 36 (90 ± 4.0) | 30 (83 ± 6.1) | 20 (56 ± 4.9) |
| 0.33–5b | 25 (5) | 22 (88 ± 4.9) | 19 (86 ± 8.0) | 11 (50 ± 6.4) |
| B, 2-cell embryosc | ||||
| None (Control) | 20 (4) | 20 (100) | – | 16 (80 ± 11.5) |
| Solution control | 20 (4) | 20 (100) | – | 17 (85 ± 9.6) |
| 0.33–4b | 25 (5) | 23 (92 ± 4.9) | – | 20 (88 ± 8.0) |
The number and percentage that are morphologically normal is Columns 3/2. The numbers and percentages that are functionally viable are Columns 4/3 and 5/3
After vitrification, the oocytes were exposed to freshly collected sperm diluted to a concentration of 3 × 106/ml with Cook Fertilization medium. The sperm concentration is critical (see text)
These two solutions yielded about the highest morphological survivals after vitrification of those tried. They are both modified 3-fold dilutions of standard full strength EAFS-10–10 vitrification solution with the compositions given in Table 1. The oocytes in those solutions were cooled to −196°C at ~69,000°C/min and warmed by laser at an estimated 1.0 × 107°C/min. Samples of 2-cell embryos were also warmed 100-times more slowly at 105 °C/min. Only 5% were morphologically normal and 0/20 developed to expanded blastocysts.
Fresh 2-cell embryos collected from the oviducts of mated females.