Can we justify spermatid microinjection for severe male factor infertility?

Area of Science:

• Reproductive Biology
• Andrology
• Embryology

Background:

• First human pregnancies via round spermatid (ROSI) and elongated spermatid (ELSI) injections reported in 1995-1996.
• Animal studies showed normal offspring, but human applications sparked ethical and scientific debate.
• Concerns exist regarding spermatid maturity and clinical implications of using immature sperm.

Purpose of the Study:

• Review current arguments on clinical ROSI and ELSI use.
• Evaluate key spermatozoon components for embryo development (genetic material, microtubular organizing complex, oocyte activating factor).
• Consider testicular histopathology and outcomes relative to ICSI birth rates.

Main Methods:

• Literature review of spermatid injection techniques and outcomes.
• Analysis of biological factors in sperm contributing to embryo development.
• Comparative assessment of ROSI/ELSI with Intracytoplasmic Sperm Injection (ICSI).

Main Results:

• Spermatid injections have resulted in pregnancies and live births, though with ongoing debate.
• Biological evaluation highlights genetic material, microtubular organizing complex, and oocyte activating factor roles.
• Histopathological findings and current birth rates from ROSI/ELSI are discussed in relation to ICSI.

Conclusions:

• The clinical application of ROSI and ELSI remains controversial due to biological and ethical considerations.
• Further investigation into spermatid biology and outcomes is warranted.
• The potential for future clinical trials for infertile men is considered.