Impact of a microfluidic-based selection device on sperm deoxyribonucleic acid fragmentation and intracytoplasmic sperm injection cycles.

OBJECTIVE

To determine the impact of a microfluidic-based sperm selection device on sperm parameters and embryo variables compared with the conventional swim-up method in sibling oocytes.

DESIGN

Prospective observational study.

SUBJECTS

A total of 345 oocytes were recruited from 27 couples undergoing intracytoplasmic sperm injection, including both own (n = 195) and donation (n = 150) cycles. None of the patients presented severe male factor.

INTERVENTION/EXPOSURE: Semen sample was divided into 2 groups and processed using swim-up or the microfluidic sperm selection device (MSSD) ZyMōt. Half of the oocytes were inseminated with swim-up-selected spermatozoa, and the rest were inseminated with MSSD-selected spermatozoa. Embryo development was followed by time-lapse. Sperm deoxyribonucleic acid (DNA) fragmentation was measured using the sperm chromatin dispersion test, analyzed with ImageJ. A Mann-Whitney U test was performed for statistical analysis.

MAIN OUTCOME MEASURES

Sperm DNA fragmentation levels, sperm parameters, fertilization rates, embryo morphokinetics, and rate of usable blastocysts.

RESULTS

Sperm DNA fragmentation was significantly lower in the MSSD group than in the swim-up group (20.3% vs. 11%), indicating a better selection. Analyzing separately the oocytes from the patient's own cycles, MSSD showed a significantly higher rate of usable blastocysts per fertilized oocyte. However, this difference was not observed using donated oocytes or when both cycles were combined. Embryos from the swim-up group showed a significant delay in time of pronuclear appearance and morula formation compared with those from the MSSD group, being more marked in donated oocytes. No significant differences were observed in the fertilization rate and the remaining morphokinetic times.

CONCLUSION

This study provides valuable information on the use of MSSD for noninvasive sperm selection. When MSSD was used, we observed a reduction in sperm DNA fragmentation and an enhancement in the number of usable embryos in our own cycles. These findings could be compatible with a reduced capacity to repair sperm damage due to poorer oocyte quality caused by advanced age.