Flow cytometric sorting of human sperm: MicroSort clinical trial update

Area of Science:

• Reproductive biology
• Genetics
• Assisted reproductive technology

Background:

• MicroSort technology offers sperm separation based on X and Y chromosomes.
• This technique is utilized for genetic disorder risk reduction and family balancing.
• Previous studies have not comprehensively summarized MicroSort's clinical efficacy and outcomes.

Purpose of the Study:

• To evaluate the efficacy of MicroSort in separating X- and Y-chromosome bearing sperm.
• To assess clinical outcomes, including pregnancy and miscarriage rates, following sperm sorting.
• To determine the sex of resulting offspring and evaluate congenital malformation incidence.

Main Methods:

• Sperm were stained with Hoechst 33342 and sorted using flow cytometry (XSort and YSort).
• Post-sort purity was assessed using fluorescence in situ hybridization (FISH).
• Clinical outcomes (IUI, IVF/ICSI, FET) and infant health records were analyzed.

Main Results:

• Post-sort purity averaged 87.9% for XSort and 73.4% for YSort.
• Pregnancy rates were 15.6% (IUI), 32.0% (IVF/ICSI), and 33.3% (FET).
• Offspring sex ratios were 92.0% female with XSort and 81.5% male with YSort; major congenital malformations occurred at a 2.6% rate.

Conclusions:

• MicroSort effectively enriches X- and Y-chromosome bearing sperm populations.
• Clinical outcomes and congenital malformation rates are comparable to those using unsorted sperm.
• The technology reliably influences the sex of resulting offspring, supporting its use in specific reproductive contexts.