Assisted Oocyte Activation (AOA) in Recurrent Fertilization Failure

Background: Despite the high success rate of ICSI, total fertilization failure still occurs in 1-3% of all ICSI cycles and can recur in subsequent cycles, even when a sufficient number of oocytes and motile spermatozoa are available. Several reports show that the majority of couples suffering from ICSI failure benefit from the application of ICSI combined with assisted oocyte activation. A variety of artificial activating methods is used in human assisted reproduction treatment, including physical, mechanical or chemical stimuli, which provoke one or more calcium rises in the oocyte cytoplasm. Study Design: Randomized controlled trial. Setting: A university fertility center. Methods: 150 infertile patients who underwent ICSI and all had history of recurrent fertilization failure. The patients were randomly allocated into 2 equal groups. Group1=75 patients who underwent ICSI without oocyte activation. Group2 patients =75 and underwent ICSI Patient underwent ICSI with oocyte activation. Reproductive outcomes were compared between both groups. Results: there were significant differences between groups regarding number of oocytes retrieved, number of mature oocyte, fertilization rate and pregnancy rate. Conclusion: Assisted oocyte activation with calcium ionophore results in significant improvement in the fertilization, cleavage and pregnancy rates after ICSI.