High reliability of morphokinetic annotations among embryologists.

Area of Science:

• Reproductive medicine
• Embryology
• In vitro fertilization (IVF)

Background:

• Morphokinetic analysis of human embryo development is increasingly used in IVF.
• Time-lapse videos (TLS) are annotated by embryologists for embryo selection algorithms.
• Reliability of these annotations among different operators is not fully established.

Purpose of the Study:

• To assess the comparability of morphokinetic measurements among different operators using time-lapse videos of human embryos.
• To determine the reliability of morphokinetic annotations in IVF laboratories.

Main Methods:

• Six embryologists annotated 93 time-lapse videos of human embryo development.
• Annotations included key developmental events like polar body extrusion and cleavage times (t2-t5).
• Inter- and intra-observer agreement was evaluated using intra-class correlation coefficients (ICCs).

Main Results:

• High inter-observer agreement (ICCs > 0.80) was found for most measured events, including t2, t3, t4, t5, and pronuclei disappearance.
• Lower agreement was observed for second polar body extrusion (ICC=0.51) and pronuclei appearance (ICC=0.63).
• Intra-observer agreement was also high, with ICCs generally above 0.80.

Conclusions:

• Morphokinetic measurements of human embryos using TLS are highly reliable both within and among different operators.
• The consistency supports the objective use of these measurements in embryo selection algorithms.
• Further studies are needed for developmental stages beyond the 6-cell stage.