Comparative study between two techniques for artificial shrinkage of blastocysts prior to vitrification: LASER pulse versus micro-needle technique in increasing chemical, clinical pregnancy and live birth rates after ICSI, a randomized controlled trial.

Purpose: This work investigates ICSI outcome between LASER Artificial Shrinkage (LAS) and Micro-Needle Artificial Shrinkage (MNAS) before vitrification.

Patients and methods: Four hundred and nine women were included in the study; which were randomly divided into two groups according to the technique used for artificial shrinkage step of the blastocyst before vitrification: in the first group, Laser beam was used while in the second group the micro-needle was used. Ovarian stimulation was done before the ICSI procedure either by long, short or antagonist protocol.

Results: The statistical analysis of our study revealed that there was no statistically significant difference between the two groups regarding age, number of cases, AMH, Basal FSH, BMI, male factor, usage ovarian stimulation protocol, high quality blastocysts, the mean number of transferred embryos. While, there was a statistically significant difference between two groups after thawing with p-value < .001 in favor of the LAS method regarding the morphology of originally high quality blastocysts, blastocysts healthiness (not degenerated), pregnancy rate, the implantation rates.

Conclusion: LASER artificial shrinkage of human blastocysts is a promising technology that could be implemented on a wider basis to improve ART practice, as our study revealed that the usage of LASER pulse for artificial shrinkage of blastocysts before vitrification has better implantation rate as well as better chemical and clinical pregnancy rate in comparison to the usage of micro-needle artificial shrinkage of blastocysts before vitrification. There is a statistically significant difference regarding live birth rate being more in the LASER group as compared to needle group, also the number of twins ether identical or non-identical are larger in laser group than in needle group but with no statistically significant difference. Clinical trials.gov ID: NCT04125017.