Increasing the probability of selecting chromosomally normal embryos by time-lapse morphokinetics analysis

Area of Science:

• Reproductive biology and genetics
• Embryology
• Assisted reproductive technology

Background:

• Preimplantation genetic screening (PGS) is crucial for IVF success.
• Identifying chromosomally normal embryos noninvasively can improve implantation rates.
• Embryo development kinetics may offer insights into chromosomal status.

Purpose of the Study:

• To investigate kinetic differences between chromosomally normal and abnormal embryos.
• To develop an algorithm for noninvasive selection of chromosomally normal embryos.

Main Methods:

• Retrospective cohort study of 504 embryos from 125 PGS patients.
• Embryo culture and monitoring using time-lapse imaging.
• Analysis of kinetic variables including cell cleavage times and cell cycle durations.

Main Results:

• Time to 5 cells (t5 - t2) and third cell cycle length (cc3) were significant predictors of normal chromosomal content.
• A proposed algorithm classified embryos into categories A-D, with significant differences in normal embryo rates (A: 35.9%, B: 26.4%, C: 12.1%, D: 9.8%).

Conclusions:

• Embryo kinetic behavior differs between chromosomally normal and abnormal embryos.
• The developed algorithm aids in classifying embryos based on kinetic data.
• This tool enhances the probability of noninvasively selecting chromosomally normal embryos for transfer.