The Infl uence of Early Cleavage Embryos afterIntracytoplasmic Sperm Injection (ICSI) on the IVF-ETOutcome

Overview

Objective:
To evaluate the infl uence of early cleavage in embryos obtained using ICSI on the successrate of IVF -⁠ ET.Design: A prospective study.Setting: Centre of Assisted Reproduction, Department of Obstetrics and Gynecology, MedicalFaculty, Palacký University, Olomouc.Methods: The rate of the fi rst cleavage of embryos was checked between 23 to 26 hours after ICSIin 115 cycles IVF -⁠ ET. „Early Cleavage“ (EC) embryos which were already cleaved were cultivatedseparately from the „slow“ (No Early Cleavage, NEC) embryos. After 3 days cultivation, no morethan three 6 -⁠ to 8-cell embryos were transferred. Only EC embryos were transferred in 43 cyclesand only NEC embryos were transferred also in 43 cycles. The remaining 29 cycles, where bothEC and NEC embryos had to be transferred, were not evaluated. In both groups the followingentry parameters were compared: age of the patient, number of fertilized oocytes, fertilizationrate (FR), number of frozen and evaluated embryos, number of EC embryos recorded and numberof transferred embryos. The outcome parameters compared were: pregnancy rate (PR), numberof gestational sacs with heart beats per number of transferred embryos (implantation rate, IR),abortions (AB) and the frequency of multiple pregnancy. Statistical evaluation was performed byt-test, χ2 test and by Sheffe analysis.Results: EC embryos were found in 57 % of cycles (n=66) after ICSI. Early cleavage was observedin 198 of 563 embryos (35%). Among entry parameters the only statistically signifi cant differences(P0.05) becauseof small numbers.Conclusion: The speed of the fi rst cell cleavage is a useful additional criterion for better evaluationof quality and viability of embryos.

Key words:
early cleavage“ embryos, embryo selection, embryo quality and viability, in vitrofertilization