Men over 60 who pay for sex use less protection and purchase more sex as they age, new research has revealed.

According to lead study author Dr Christine Milrod, among American men between ages 60 and 84 who pay for sex, it was found that the older they were, the more frequently they paid for sex.

They were also more likely to have experienced unprotected sexual intercourse multiple times with their favourite commercial sex providers.

"There is a nearly universal perception that older men do not pay for, or even engage sexually with regular frequency," said Dr Milrod.

This view may contribute to a false sense of security for both clients and sex workers during their encounters, and may lead to less protective strategies than with younger purchasers of sex.

"In addition, the exchange of emotional intimacy during the so-called 'Girlfriend Experience' as well as the possibility of being viewed as an elderly low-risk client may contribute to a relaxation of boundaries and a false sense of security in avoiding sexually-transmitted infections (STIs)," Milrod explained.

Using various sex provider review websites and discussion boards, Dr. Christine Milrod and University of Portland sociology professor Martin Monto surveyed 208 men between the ages of 60 and 84 who solicited sex workers in order to assess their condom use and sexual risk taking.

The researchers found that 59.2 percent reported not always using protection with sex workers.

Nearly 95 percent reported avoiding protection for manual masturbation and 91 percent reported avoiding protection for oral sex.

While 31.1 percent reported having been diagnosed with an STI at some point during their lifetime, 29.2 percent reported having an "all-time favourite" sex provider with whom they engage repeatedly.

Being more emotionally attached to sex workers was positively related to more unprotected sex.

To reduce the incidence of STIs among sexually active older men, Milrod and Monto suggest that health care providers ask their older male patients about their sexual partners and discuss protective strategies for avoiding STIs.

"Medical and mental health clinicians should not assume that old age is a barrier to paying for sex, particularly among the generations that began engaging in sexual activity prior to the epidemic emergence of the HIV virus," they noted in a new study published in the American Journal of Men's Health (a SAGE journal).