Objective: To present the effectiveness of intracytoplasmic sperm injection (ICSI) using globozoospermic sperm and assisted oocyte activation by electrical stimulation.
Design: A case report.
Setting: A private IVF center in Japan.
Patient(s): A man with globozoospermia.
Intervention(s): Acridine orange (AO) test, mouse oocyte activation test, and ICSI with electrical oocyte activation.
Main outcome measure(s): Fertilization, pregnancy, and live birth.
Result(s): In the first ICSI attempt, neither of the two injected oocytes fertilized. Staining of the patient's sperm with AO showed that only 2.9% of the sperm emitted a green fluorescence at the characteristic round head (sperm with native DNA content). The mouse oocyte activation test using the roundheaded sperm showed that the normal fertilization rate was 78.9% when SrCl(2) was used for assisted oocyte activation; however, it was 6.0% without assisted oocyte activation. We confirmed that the sperm had defective ability to activate oocytes. In the second ICSI attempt, human oocytes were activated electrically with use of a single square direct current pulse after microinjection. All the seven injected oocytes fertilized normally, and two eight-cell embryos were transferred on day 3. Clinical pregnancy was confirmed, and a healthy girl weighing 2362 g was delivered at 37 weeks of gestation by cesarean section.
Conclusion(s): This is the first successful outcome of ICSI using globozoospermic sperm and electrical oocyte activation. The electroactivation obviates the need for the use of potentially harmful drugs for activation.