Figure 1.

The effects of embryo culture on developmental viability. (A) Hybrid strain (B6CBF1) zygotes collected 20 h post-hCG or (B) 2-cell embryos 44 h post-hCG were cultured as 10 embryos in a drop of 10 μL GE-HTF medium or sIVF media under 5% CO₂ in air (20% O₂). The cell number of the cultured embryos and the embryos freshly collected from reproductive tracts at a 12 h interval from (A) 36 h post-hCG or (B) 60 h was recorded. Each time point is the record of least 80 embryos from 3 independent replicates. *p < 0.001, compared to the corresponding stage of cultured embryo. (C) Representative images of embryos stained with Hoechst 33342 and examples of fragmented nuclei shown with arrows.