All procedures involving animal models have been reviewed by the local institutional animal care committee and the JoVE veterinary review board.

1. Embryo Warming

1. Thaw the embryos in a single step.
   1. Place the ministraw horizontally 10 cm from liquid nitrogen vapour for 20-30 s.
   2. When the crystallization process begins inside the ministraw, immerse the ministraw in a water bath at 25°C for 10-15 s.
   3. Remove the ministraw plug and cut the cotton plug.
   4. With a coupled microdispenser, expel all the ministraw content into a plate containing 0.33 M sucrose solution at 25°C in BM for 5 minutes.
      NOTE: This step must be done quickly in order to reduce embryo exposure to the vitrification solution. 
   5. Move the embryos to a new plate containing BM solution for another 5 min.