Objective: To examine whether sperm-borne and oocyte-borne oocyte activation failures can be overcome by mechanical means that entail modifying the ICSI technique.
Design: Case report series.
Setting: Private clinics.
Patient(s): Six infertile couples undergoing ICSI.
Intervention(s): Standard ICSI and modified ICSI based on mechanical manipulation that facilitated entry of calcium into the oocyte.
Main outcome measure(s): Fertilization rate and pregnancy outcome.
Result(s): In three cases of sperm-borne and three cases of oocyte-borne oocyte activation deficiencies, the modified ICSI technique enabled normal fertilization and development of embryos with good morphology. In terms of fertilization, the efficacy of modified ICSI was similar to use of a calcium ionophore, without producing extensive embryo fragmentation during postfertilization development. Term pregnancies resulting in the birth of normal children were achieved with the modified ICSI technique in five cases.
Conclusion(s): Sperm-borne and oocyte-borne oocyte activation failures can be overcome by modifying the ICSI technique. The modification obviates the need to use insufficiently tested and potentially harmful drugs.