Circumcising men may significantly reduce the rate of cervical cancer in women by decreasing the spread of a sexually transmitted virus that causes nearly all cases of cervical cancer, researchers are reporting.

A study being published today in The New England Journal of Medicine provides important scientific evidence for a link that scientists have long suspected.

The new findings are based on 1,913 couples in five countries, including 977 couples in which the woman had cervical cancer and 936 couples without cancer. Researchers found that circumcision made a difference if the man had had six or more sex partners, which made him more likely to have contracted the cancer-causing human papilloma virus, or H.P.V. In those couples, the risk of cervical cancer was more than double if the man was not circumcised.

The findings may not apply to couples in which the man has had fewer than six sex partners, because he is less likely to be carrying H.P.V.

The researchers say uncircumcised men may be more likely than others to contract H.P.V. because the lining of the foreskin is especially vulnerable to the virus. Their study, which used DNA testing to look for penile H.P.V. infection in the men, found that uncircumcised men were about three times as likely as circumcised men to be infected.

Circumcision