Understanding fertilization through intracytoplasmic sperm injection (ICSI)

Queenie V. Neri, Bora Lee, Zev Rosenwaks, Khaled Machaca, Gianpiero D. Palermo

Research output: Contribution to journalReview article

54 Citations (Scopus)


Since the establishment of in vitro fertilization, it became evident that almost half of the couples failed to achieve fertilization and this phenomenon was attributed to a male gamete dysfunction. The adoption of assisted fertilization techniques particularly ICSI has been able to alleviate male factor infertility by granting the consistent ability of a viable spermatozoon to activate an oocyte. Single sperm injection, by pinpointing the beginning of fertilization, has been an invaluable tool in clarifying the different aspects of early fertilization and syngamy. However, even with ICSI some couples fail to fertilize due to ooplasmic dysmaturity in relation to the achieved nuclear maturation marked by the extrusion of the first polar body. More uncommon are cases where the spermatozoa partially or completely lack the specific oocyte activating factor. In this work, we review the most relevant aspects of fertilization and its failure through assisted reproductive technologies. Attempts at diagnosing and treating clinical fertilization failure are described.

Original languageEnglish
Pages (from-to)24-37
Number of pages14
JournalCell calcium
Issue number1
Publication statusPublished - Jan 2014



  • Assisted oocyte activation
  • Calcium influx
  • Failed fertilization
  • ICSI
  • Oocyte activation
  • PLCζ
  • Sperm cytosolic factor

ASJC Scopus subject areas

  • Physiology
  • Molecular Biology
  • Cell Biology

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