DNA Fragmentation Index

DNA fragmentation index (DFI) is a measurement used to determine the amount of sperm that have abnormal genetic material.

Sperm contains half of the DNA required to fertilize an egg. If the DNA in sperm is damaged, it may be unable to fertilize the egg, or if fertilization occurs, the resulting embryo may fail to progress normally or properly implant into the uterine lining.

A DFI above 30% is related to infertility and above 20% is considered to be suboptimal. One study found that in couples with unexplained infertility 26% of men had a DFI of 20% or greater.