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Updated: Aug 6, 2026

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Published on: January 26, 2024
Intracytoplasmic sperm injection increases embryo fragmentation without affecting clinical outcome
J L Frattarelli1, M P Leondires, B T Miller
1Department of Obstetrics and Gynecology, Walter Reed Army Medical Center, Washington, DC 20307-5001, USA.
Purpose:
To examine the effect of intracytoplasmic sperm injection (ICSI) on embryo fragmentation and implantation rates in those embryos chosen for transfer compared to conventional in vitro fertilization (IVF).
Methods:
We compared 253 infertility patients (71 ICSI and 182 IVF) with respect to age, semen analysis, number of embryos transferred, embryo fragmentation, implantation rate, and pregnancy rate. Embryo fragmentation was determined by one observer at the same laboratory over the entire study period.
Results:
A statistically significant difference was observed in mean embryo grade between IVF (2.2 +/- 0.84) and ICSI (2.5 +/- 0.77), P = 0.01. Additionally, the IVF patients had significantly more nonfragmented (grade I) embryos compared to the ICSI group, P < 0.01.
Conclusions:
These data suggest that ICSI, irrespective of semen parameters, may increase embryo fragmentation and produce fewer nonfragmented grade I embryos while maintaining implantation and pregnancy rates similar to conventional IVF.
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