Pregnancy rates are higher with intracytoplasmic morphologically selected sperm injection than with conventional intracytoplasmic injection

Fertil Steril. 2003 Dec;80(6):1413-9. doi: 10.1016/j.fertnstert.2003.05.016.


Objective: To verify whether microinjection into retrieved oocytes of motile spermatozoa with morphologically normal nuclei, strictly defined by high power light microscopy (x >6000), improves the IVF/intracytoplasmic sperm injection (ICSI) pregnancy rate in couples with repeated ICSI failures.

Design: Comparative prospective study testing routine IVF/ICSI outcome parameters against those of modified ICSI based on morphological selection of spermatozoa with normal nuclei.

Setting: Male factor fertility laboratory and IVF center.

Patient(s): Sixty-two couples, with at least two previous consequent pregnancy failed ICSI cycles, underwent a single ICSI trial preceded by morphological selection of spermatozoa with normal nuclei. Fifty of these couples were matched with couples who underwent a routine ICSI procedure at the same IVF center and exhibited the same number of previous ICSI failures.

Intervention(s): Standard ICSI and modified ICSI.

Main outcome measure(s): ICSI pregnancy rate.

Result(s): The matching study revealed that pregnancy rate after modified ICSI was significantly higher than that of the routine ICSI procedure (66.0% vs. 30.0%).

Conclusion(s): Microinjection into retrieved oocytes of selected spermatozoa with strictly defined morphologically normal nuclei improves significantly the incidence of pregnancy in couples with previous ICSI failures.

Publication types

  • Clinical Trial
  • Comparative Study
  • Controlled Clinical Trial

MeSH terms

  • Adult
  • Female
  • Fertilization in Vitro / methods
  • Humans
  • Infertility, Male / therapy
  • Male
  • Microinjections
  • Oocytes / cytology*
  • Pregnancy
  • Pregnancy Outcome*
  • Sperm Count*
  • Sperm Injections, Intracytoplasmic*
  • Spermatozoa / cytology*
  • Spermatozoa / pathology
  • Treatment Failure