Figure 4

Experimental set-up. Experiment 1: After in vitro maturation (IVM) and in vitro fertilization (IVF), presumed zygotes derived from fresh cumulus enclosed oocytes were divided for in vitro culture (IVC) between traditional group culture (n = 582) and Well of the Well (WOW) time-lapse system (n = 351) to evaluate developmental potential and morphokinetics during all culture (8 days). Experiment 2: After IVM, oocytes were divided in 4 groups, Control: fresh cumulus enclosed oocytes (n = 709); Corona radiata (CR): fresh oocytes partially denuded to leave only the CR (463). VCR-H: CR oocytes vitrified with a protocol using high concentrations of cryoprotectants (15%) in equilibration solution (n = 274); VCR-L: CR oocytes vitrified with a protocol using a low cryoprotectants concentration (3%) in equilibration solution (n = 330). After IVF they were split in Group culture and WOW time-lapse for developmental and morphokinetics analyses. Experiment 3: Presumptive zygotes were cultured in WOW time-lapse systems, and collected immediately after the first cleavage, they were classified as bipolar (cleaved in two cells; n = 22) or multipolar (cleaved directly in three or more; n = 20) division, zona pellucida was removed and individual blastomeres were measured, fixed, and stained with Hoechst 33342 for nuclear evaluation.