Fig. 1.

The well-of-the-well (WOW) system for group embryo culture. (A) Preparation of the WOW system. The wells were made manually with a strong mechanical force using a BLS aggregation needle under paraffin oil (a). The 9 wells were made in 50 μl medium droplets under paraffin oil (b). Scale bar indicates 2 mm. (B) Schematic drawing of cross-sectional profiles for two culture systems. The medium droplets (50 μl each) covered by paraffin oil on flat surface of Petri dish (a). The medium droplets (50 μl each) with the WOW system on the bottom of the Petri dish, covered by paraffin oil, each well containing an embryo (b)