JBRA Assist. Reprod. 2025;29(Suppl 1):53-53
POSTER PRESENTATION
doi: 10.5935/1518-0557.20250107
1Fertya Medicina Reproductiva, Rosario, Argentina
1Co-AuthorsObjective: The objective of this study was to evaluate whether the assisted hatching (AH) technique improves implantation and clinical pregnancy rates in patients with recurrent implantation failure in frozen embryo transfer cycles.
Methods: Patients from the Fertya Reproductive Medicine clinic, located in Rosario, Argentina, were included in the study. All patients had experienced at least two failed single-blastocyst embryo transfers between 2023 and March 2025 (n=128). All selected patients followed homogeneous endometrial preparation protocols in both their previous and current cycles, allowing for their inclusion in the study. Patients with difficult transfers, bleeding, and/or re-transfers were excluded. For the assisted hatching technique, a laser system (Lycos Hamilton Thorne) coupled to an inverted microscope was used. Assisted hatching was performed by applying controlled pulses of laser energy (7 pulses/sec with 200 µs power), ensuring precise zona pellucida opening without compromising embryo viability. The embryos selected for transfer were at the blastocyst stage, and in all cases, a single embryo transfer (SET) was performed to reduce the risk of multiple pregnancies and improve perinatal outcomes. Embryo implantation was determined by measuring β-hCG hormone levels in maternal serum, with values above 50 mIU/ml considered positive. Clinical pregnancy was defined as the presence of an intrauterine gestational sac visualized by transvaginal ultrasound in early pregnancy stages. Chi-square and Irwin-Fisher tests were used to compare the study groups. Statistical significance was set at p<0.05.
Results: Before comparing the groups (AH vs. no AH), the D’Agostino-Pearson test was performed to assess demographic data homogeneity. The population was found to be homogeneous and comparable, allowing for group comparison. The results showed that although there was no significant difference in the implantation rate between embryos that underwent AH and those that did not (37.0% vs. 29.0%; p = 0.350), a positive effect on the clinical pregnancy rate was observed. Statistical analysis using the Irwin-Fisher exact test revealed a significant difference in favor of the AH group (30.0% vs. 17.2%; p = 0.023).
Conclusion: These results suggest that assisted hatching may play a relevant role in improving clinical pregnancy rates in patients with more than two failed embryo transfers. Further research is essential to identify specific patient subgroups that may benefit the most from this technique, optimizing assisted reproduction protocols and improving clinical outcomes.