Fertilization and pregnancy after assisted oocyte activation and intracytoplasmic sperm injection in a case of round-headed sperm associated with deficient oocyte activation capacity.

OBJECTIVE: To investigate a method of assisted activation of human oocytes for the treatment of infertility resulting from globozoospermia associated with deficient oocyte activation capacity.
DESIGN: The mouse oocyte activation test was used to analyze the oocyte activation capacity of the sperm cells of a patient with globozoospermia. Fresh donor human oocytes were used for determining the most appropriate procedure for oocyte activation.
SETTING: Infertility Center, University Hospital of Ghent. PATIENT(S): A couple with infertility resulting from globozoospermia. INTERVENTION(S): Intracytoplasmic sperm injection, assisted oocyte activation, and embryo transfer. MAIN OUTCOME MEASURE(S): Oocyte activation and fertilization rates, implantation, and pregnancy. RESULT(S): Deficiency in oocyte activation capacity was found in the sperm of a patient with globozoospermia. This deficiency was proven by the mouse oocyte activation test and was confirmed further by lack of activation of human oocytes after simple sperm injection. Only human oocytes that were injected with sperm and subjected to calcium chloride and ionophore treatment underwent activation. Transfer of embryos obtained by this procedure of assisted oocyte activation resulted in an ongoing pregnancy. CONCLUSION(S): Assisted oocyte activation of human oocytes is useful when globozoospermia is associated with absence of oocyte activation capacity in the sperm. These cases can be identified by the mouse oocyte activation test.