Intracytoplasmic sperm injection: a novel selection method for sperm with normal frequency of chromosomal aneuploidies.

OBJECTIVE To test a newly invented intracytoplasmic sperm injection (ICSI) sperm selection method based on sperm hyaluronic acid (HA) binding. DESIGN Comparison of chromosomal disomy and diploidy frequencies in sperm arising from semen and in HA-bound sperm. SETTING Academic andrology laboratory. PATIENT(S) Men presenting for semen analysis. INTERVENTION(S) Washed sperm fractions of 32 semen samples were applied to Petri dishes or glass slides coated with immobilized HA. The unbound sperm were rinsed gently, and the HA-bound sperm were removed with an ICSI pipette. The control sperm population was the unselected sperm. Both HA-selected and unselected sperm were treated with fluorescence in situ hybridization with centromeric probes for the X, Y, and 17 chromosomes. MAIN OUTCOME MEASURE(S) Chromosomal disomy and diploidy frequencies. RESULT(S) In the HA-bound sperm (495-2,079 per man, 41,670 in all) compared with unselected sperm (4,770 per man, 162,210 in all), the chromosomal disomy frequencies were reduced to 0.16% from 0.52%, diploidy to 0.09% from 0.51%, and sex chromosome disomy to 0.05% from 0.27% (a 5.4-fold reduction vs. 4-fold respective increase in ICSI offspring). CONCLUSION(S) The HA sperm selection method for ICSI, which is based on a relationship between sperm receptors for zona pellucida and HA, will likely reduce the potential genetic complications and adverse public health effects of ICSI.