Table 2.
The effect of different processing steps of semen cryopreservation on sperm plasma membrane (PM) and acrosome reaction (AR) examined by transmission electron microscopy.
| Sample | Slightly swollen PM |
Swollen PM |
Lost PM |
||||||
|---|---|---|---|---|---|---|---|---|---|
| P% | OR | CI (95%) | P% | OR | CI (95%) | P% | OR | CI (95%) | |
| Diluted (37°C) | 16a | 2a | 2a | ||||||
| Cooled (4°C, 2 h) | 21a | 1.40 | 0.68–2.87 | 2a | 1.00 | 0.14–7.24 | 2a | 1.00 | 0.14–7.24 |
| Equilibrated (4°C, 4 h) | 22a | 1.48 | 0.73–3.02 | 15b | 8.65 | 1.92–38.90 | 3a | 1.52 | 0.25–9.27 |
| Frozen-thawed (37°C) | 10 a | 0.58 | 0.25–1.36 | 40c | 32.67 | 7.62–140.1 | 10b | 5.44 | 1.16–25.52 |
| Sample | Typical AR | Atypical AR | Lost acrosome | ||||||
| P% | Exact Sig.* | P% | OR | CI (95%) | P% | OR | CI (95%) | ||
| Diluted (37°C) | 0a | 9a | 1a | ||||||
| Cooled (4°C, 2 h) | 0a | 1.000 | 14a | 1.64 | 0.67–3.99 | 1a | 1.00 | 0.62–16.2 | |
| Equilibrated (4°C, 4 h) | 3a | 0.246 | 16a | 1.93 | 0.81–4.59 | 1a | 1.00 | 0.62–16.2 | |
| Frozen-thawed (37°C) | 10b | 0.002 | 19b | 2.37 | 1.06–5.54 | 6a | 6.32 | 0.74–53.5 | |
Data are shown as the “P” proportions of each parameter per 100 sperm counted in each sample. OR: Odds ratio and CI (95%): confidence interval are shown in comparison to freshly diluted semen at 37°C. Different alphabet superscripts within each column indicate significant different at P < .05 as analyzed by logistic regression (Wald test).
*
Typical AR was analyzed using 2-tailed Fisher exact test because the probability of 2 groups equals zero.