Lack of sperm coating plays role in infertility

July 20, 2011 - 1:44 PM

WASHINGTON (AP) — Scientists have found a new contributor to male infertility, a protein that's supposed to coat sperm to help them swim to an egg — unless that coating goes missing.

Researchers say about 20 percent of men may harbor a gene mutation that leaves their sperm uncoated and thus lowers their fertility.

Wednesday's study tracked 500 Chinese couples who were attempting to conceive, and found birth rates were 30 percent lower if the husband harbored the mutation.

The University of California, Davis, researchers say it should be easy to create a test to diagnose the problem so that couples could try treatments to bypass it — such as having sperm placed directly into the woman's uterus.