Related Experiment Video
Updated: Aug 29, 2026

Mouse Round Spermatid Injection
Published on: January 26, 2024
Pregnancy rates are higher with intracytoplasmic morphologically selected sperm injection than with conventional
Benjamin Bartoov1, Arie Berkovitz, Fina Eltes
1Male Fertility Laboratory, Faculty of Life Sciences, Bar-Ilan University, Ramat Gan, Israel. bartoob@mail.biu.ac.il
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.
