Objective: To study the association between low percentages of intact sperm
acrosomes and fertilization failures in conventional IVF procedures.
Design: A retrospective study.
Setting: Clinical and academic research environment.
Patient(s): Patients undergoing treatment of infertility.
Intervention(s): Sperm cells were fixed and stained using the Spermac stain
.
Main Outcome Measure(s): Percentages of intact acrosomes and fertilization.
Result(s): There was a significant association between specimens with <40%
intact acrosomes and failed conventional IVF procedures. Among the 29 cases
with <40% intact acrosomes, 9 cases (31%) resulted in zero penetration of
the oocytes. The mean (+/-SEM) percentage of fertilization was lower in the
abnormal kacrosome group (43.3% +/- 6.5%) than in the normal acrosome grou
p (64.1% +/- 5.6%). The status of the sperm acrosome was not correlated wit
h the results of fertilization in intracytoplasmic sperm injection procedur
es.
Conclusion(s): Sperm with low percentages of intact acrosomes were associat
ed with failed fertilization. The Spermac stain was useful for assessing ac
rosomes and identifying possible male factor infertility problems. The resu
lts suggested that a minimum percentage of sperm with intact acrosomes are
needed for fertilization to occur in vitro. (Fertil Steril(R) 1999;72:124-8
. (C) 1999 by American Society for Reproductive Medicine.)