S. Benoff et al., Numerical dose-compensated in vitro fertilization inseminations yield highfertilization and pregnancy rates, FERT STERIL, 71(6), 1999, pp. 1019-1028
Objective: To evaluate in cases with morphologically abnormal sperm whether
fertilization and pregnancy rates are increased by normalizing the number
of sperm inseminated and whether biomarkers can identify cases of reduced o
r failed fertilization.
Design: Prospective studies of sperm morphology and function.
Setting: University hospital assisted human reproduction program.
Patient(s): Partners of 308 women undergoing IVF.
Intervention(s): Motile sperm populations were assessed for sperm head morp
hology, for surface receptors for mannose and progesterone binding, and the
ability to undergo a free mannose-induced acrosome reaction. Zinc in semin
al plasma was determined by atomic absorption spectroscopy.
Main Outcome Measure(s): Sperm morphology was associated with fertilization
and clinical pregnancy rates. Biomarker analyses were correlated with fert
ilization rates using Kruskal-Wallis tests, chi(2) tests, and Spearman rank
order correlations.
Result(s): Fertilization and pregnancy rates after numerical dose compensat
ion inseminations were indistinguishable between men with differing percent
ages of normal sperm. Biomarker deficits were identified irrespective of sp
erm head morphology in 96% of cases of reduced or failed fertilization.
Conclusion(s): Fertilization and pregnancy rates in cases of abnormal morph
ology are optimized by inseminating at least 25,000 sperm/mL with normal ac
rosomes. Reduced or failed fertilization can be predicted by testing for mo
lecular deficits in mannose receptor expression and mannose-stimulated acro
some loss. (Fertil Steril(R) 1999;71:1019-28. (C) 1999 by American Society
for Reproductive Medicine.).