Assessment of the dominant abnormal form is useful for predicting the outcome of intracytoplasmic sperm injection in the case of severe teratozoospermia

Yoshiko Osawa, Kou Sueoka, Soukichi Iwata, Masami Shinohara, Noriko Kobayashi, Nadaki Kuji, Yasunori Yoshimura

Research output: Contribution to journalArticle

29 Citations (Scopus)


Purpose: Our purpose was to investigate the relation between the dominant sperm anomaly and sperm morphology and the outcome of intracytoplasmic sperm injection (ICSI). Methods: Two hundred ninety-five patients who underwent a total of 181 cycles of in vitro fertilization (n = 168) and/or 217 cycles of ICSI (n = 177) between July 1995 and May 1997 at Keio University Hospital were investigated. Results: The rates of fertilization and pregnancy were 63.3 and 27.8%, respectively, in ICSI cycles with ≤4% normal forms. When the percentage of strictly normal morphology was ≤4, the fertilization rate was lower in the case of severely tapered head (13.0%; n = 4) than in the cases of other deformities in ICSI. The acrosomal defect made no difference in the fertilization rate with ICSI. Conclusions: The predominant abnormal form affects the ICSI outcome in the case of ≤4% normal forms.

Original languageEnglish
Pages (from-to)436-442
Number of pages7
JournalJournal of Assisted Reproduction and Genetics
Issue number8
Publication statusPublished - 1999 Sep 7



  • Intracytoplasmic sperm injection
  • Morphology
  • Outcome
  • Teratozoospermia

ASJC Scopus subject areas

  • Reproductive Medicine
  • Genetics
  • Obstetrics and Gynaecology
  • Developmental Biology
  • Genetics(clinical)

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