Received July 13, 2019
Accepted December 15, 2019

Objective: Evaluate the recovery of thawed blastocysts submitted to quarter laser assisted hatching and to correlate with pregnancy rates. Methods: A cross-sectional study was carried out in which single blastocyst transfers were included from July 2017 to December 2018. 765 blastocysts were thawed and submitted to quarter laser assisted hatching technique was performed in the zona pellucida immediately after thaw and incubated for 3 hours until transfer time, when evaluating if they were collapsed or expanded and, if they were expanded, herniated or not. Statistical analysis was performed using the chi-square test. Results: 627 expanded (81.9%) and presented a 40% pregnancy rate (251/627). 138 collapsed blastocysts after thawing (18.0%), resulted in 25.4% (35/138) (p = 0.001) gestation. After evaluating only the expanded blastocysts, 385 herniated (61.4%) and resulted in 43.9% (169/385) of pregnancy. The 242 non-herniated blastocysts (38.6%) presented 33.9% of gestation (82/242) (p = 0.013). Statistical analysis was considered statistically significant at p <0.05. Conclusion: The quarter laser assited hatching technique proved to be safe, valid and relatively easy and could be performed on thawed blastocysts. Blastocysts with the capacity to expand and herniate after the use of this technique, presented statistically superior results.