ABSTRACT
A key technique in assisted reproductive technology (ART) is intracytoplasmic sperm injection (ICSI), whereby a sperm is microinjected directly into the oocyte cytosol. Predominantly used to treat male factor infertility follow- ing the failure of conventional in vitro fertilization (IVF), ICSI remains a successful technique that results in normal fertilization in 70% of injected oocytes. However, a noted phenomenon associated with male infertility is the failure of some oocytes to activate, with embryos failing either to protrude the second polar body or to successfully pro- ceed past the first cell division, even following ICSI. One approach to cases of failed oocyte activation after ICSI is to stimulate the oocyte artificially. So-called artificial oocyte activation (AOA) has already been attempted in many dif- ferent clinics, to varying degrees of success. Herein, we discuss oocyte activation at mammalian fertilization and relate this fundamental biological process with the clinical phenomenon of oocyte activation deficiency. We also dis- cuss the science behind the stimuli used to induce AOA, alongside future directions for treatment.
