Failure of pregnancy after intracytoplasmic sperm injection with decapitated spermatozoa: case report

The case of a couple with a history of long standing primary infertility is reported in which the man presented with a decapitated sperm defect. The woman had a normal history and presented with normal clinical characteristics. The couple underwent one unsuccessful conventional in-vitro fertilization (IVF). Subsequently, embryos were obtained and transferred after assisted fertilization attempts: in all, three subzonal inseminations and four intracytoplasmic sperm injections. A total of 49 mature oocytes was injected in both studies, 25 embryos obtained and 20 embryos transferred, three of them after freezing and thawing. Despite the good embryo morphology, implantation was unsuccessful and no pregnancy occurred. The failure of implantation may have resulted from an arrest in early embryonic development related to the sperm anomaly. One hypothesis is that transferred embryos may carry a chromosomal imbalance that prevents them from progressing to the blastocyst stage. Nevertheless, we cannot exclude the possibility that the woman is responsible for the implantation failure. Co-culture associated with a further attempt could provide information regarding the ability of embryos to progress to the blastocyst stage and implant.