The use of femtosecond laser pulses for controlled laser-assisted hatching of fresh and frozen/thawed mammalian embryos

Femtosecond laser pulses were applied for the microsurgery of mammalian embryos at the late stages of preimplantation development. An artificial opening in the outer envelope of mouse blastocysts was created and promoted hatching to start immediately through the hole formed. Laser exposure parameters were optimized to perform delicate laser-assisted hatching either on fresh or frozen/thawed embryos.