New Male Infertility Finding Reported

U.S. scientists have discovered a specific factor in immune cells regulates human semen and seems to determine whether a man will be fertile.

Yousef Al-Abed and colleagues at The Feinstein Institute for Medical Research isolated an immune substance called macrophage migration inhibitory factor, or MIF, in semen samples from infertile and reproductively healthy men.

The semen was collected from men after a period of sexual abstinence. The scientists had no idea whether a specific sample came from any of the 68 men who had problems conceiving or from the 27 healthy controls.

The researchers found those with infertility problems had MIF levels that were either too high or too low. Those who had no problems conceiving had levels that were just right.

When the scientists added MIF to lab dishes filled with healthy sperm, it decreased the count and impaired their motility.

If MIF has a role in infertility, Al-Abed and colleagues said they wonder whether it might work as a form of male contraception.

The findings, which could lead to a diagnostic test to determine fertility status, appear in the journal Molecular Medicine.