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Analysis of Epididymal Protein Synthesis and Secretion
Published on: August 25, 2018
Human sperm head vacuoles are physiological structures formed during the sperm development and maturation process
Atsushi Tanaka1, Motoi Nagayoshi, Izumi Tanaka
1Saint Mother Obstetrics and Gynecology Clinic and Institute for Assisted Reproductive Technology, Fukuoka, Japan. incho@stmother.com
Fertility and Sterility
|May 26, 2012
Summary
Human sperm head vacuoles are common but do not impact intracytoplasmic sperm injection (ICSI) success rates. This finding is crucial for understanding male fertility and improving assisted reproductive technologies.
Area of Science:
- Reproductive Biology
- Human Embryology
- Andrology
Background:
- Sperm vacuoles are frequently observed in human spermatozoa and spermatids.
- The clinical significance of these vacuoles in assisted reproduction remains unclear.
Purpose of the Study:
- To investigate the impact of human sperm vacuoles on the success rates of intracytoplasmic sperm injection (ICSI).
Main Methods:
- A retrospective study was conducted at a private infertility clinic.
- Sperm samples were collected from men with varying semen parameters (normozoospermic, oligozoospermic, asthenozoospermic, azoospermic).
- Differential interference contrast microscopy was used to assess sperm vacuoles, followed by ICSI with morphologically selected sperm.
Main Results:
- Vacuoles were present in over 97% of ejaculated sperm and a high percentage of epididymal and testicular sperm, as well as spermatids.
- Fertilization rates after ICSI using sperm with vacuoles were 60.9% (large) and 85.7% (small), with blastocyst development rates around 50%.
- Sperm without vacuoles showed an 80% fertilization rate but only 25% blastocyst development.
Conclusions:
- Human sperm head vacuoles do not adversely affect fertilization and blastocyst development rates following ICSI.
- The presence of vacuoles should not be a primary concern when selecting sperm for ICSI procedures.
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