Steps forward in embryo transfer technique: a retrospective study comparing direct versus afterload catheters at...

Area of Science:

• Reproductive Medicine
• Embryology
• In Vitro Fertilization

Background:

• Embryo transfer (ET) is a critical step in assisted reproductive technology (ART).
• The technique employed for ET can potentially influence pregnancy outcomes.
• Standardization and optimization of ET procedures are essential for improving success rates.

Purpose of the Study:

• To evaluate the impact of different embryo transfer (ET) techniques on clinical pregnancy rates (CPR).
• To investigate the correlation between ET technique and the difficulty of embryo transfer.
• To compare the 'afterload' ET technique with the 'direct' ET technique.

Main Methods:

• Retrospective cohort analysis of 8,189 fresh and frozen single blastocyst transfers (January 2016 - December 2021).
• Comparison of 'direct' ET technique (used Jan 2016 - Sept 2017) with 'afterload' ET technique (used April 2019 onwards).
• Randomized controlled trial period (Sept 2017 - March 2019) for technique selection; logistic regression analysis used.

Main Results:

• The afterload ET technique group showed a significantly higher CPR (44.69%) than the direct ET technique group (41.65%).
• The rate of difficult embryo transfers was significantly lower in the afterload group (9.06%) compared to the direct group (26.85%).
• Odds ratios indicated a 1.13 increase in CPR and a 0.27 decrease in difficult transfers for the afterload technique.

Conclusions:

• The choice of embryo transfer (ET) technique significantly affects clinical pregnancy rates (CPR).
• The afterload ET protocol is associated with improved CPR and a higher rate of easy embryo transfers.
• Optimizing ET technique, such as employing the afterload method, can enhance ART success.