The IVP rates observed with incubation in mTBM during
6 h were similar to those reported by Zhao et al. (2002),
regardless of the method of oocytes conditioning, using a
conventional CO2 incubator. The results of the present study
indicate that CO2 incubators may be unnecessary for the IVP
test, as also reported elsewhere (Corcini et al., 2012a;
Macedo et al., 2006, 2010). The greater IVP and polyspermy
rates and number of spermatozoa per oocyte observed with
mTBM than with BTS may be attributed to the high calcium
concentration in the mTBM,