A survey has found that heterosexual women are less likely to use condoms for anal sex than gay men.

The research, carried out by the New York City Department of Health, found that only 23 per cent of women required their male partners to use condoms during anal sex, compared with 61 per cent of gay or bisexual men.

According to the department, an estimated 100,000 New York City women have anal sex every year.

Women who did not use condoms were also far less likely to get tested for sexually transmitted diseases.

While 63 per cent of those who use always condoms get tested regularly, on 35 per cent of those who bareback do.

Younger women were found to be the most likely to unprotected anal sex, with 11 per cent of those aged 18 to 24 stating that they did, compared to two per cent of women aged between 45 and 62.

Anal membranes are easily damaged during sex, facilitating the spread of infection. Past studies suggest that anal exposure to HIV poses 30 times more risk than vaginal exposure.

“Tens of thousands of New Yorkers are engaging in sexual behaviour that is especially risky,” said Dr. Thomas Farley, New York City Health Commissioner.

“Many people are aware of the risk of HIV when men have sex with other men, but this report shows that a large number of women also are putting themselves at high risk through unprotected anal sex.

“For both men and women, the overall message is clear: Never engage in unprotected anal sex. Use a condom every time.”