Image copyright Thinkstock

Using smartphone apps to seek out partners for casual sex poses an increased risk of sexually transmitted infections, researchers warn.

A study in Los Angeles, California, showed gonorrhoea and chlamydia were more common in gay men using apps than in those meeting in clubs or online.

Sexual health experts said technology was creating more opportunities for sex than ever before.

One of the apps, Grindr, said it was committed to promoting safe sex.

The researchers were curious about the impact of apps such as Grindr and Scruff which use a smartphone's location to help find partners.

However good the sex is, it's not worth contracting a long-term condition Justin Harbottle, Terrence Higgins Trust

They quizzed 7,184 men attending a sexual health clinic at the LA Gay and Lesbian Centre.

The results showed men were 23% more likely to have gonorrhoea and 35% more likely to be infected with chlamydia than men using other websites or clubs to meet new partners.

There was no difference in the risk of HIV between the groups.

Their report concluded: "Technology is redefining sex on demand.

"Advances which improve the efficiency of meeting anonymous sexual partners may have the unintended effect of creating networks of individuals where users may be more likely to have sexually transmissible infections."

Condoms

Image copyright SPL Image caption Chlamydia is spread through sexual contact

Dr Steve Taylor, a consultant in sexual health and HIV medicine at Birmingham Heartlands Hospital, told the BBC: "Yes this is definitely something we are seeing in our sexual health and HIV clinics, both among gay men and heterosexuals.

"Without a doubt technology has facilitated rapid partner change and therefore it is a perfect environment for sexually transmitted infections and HIV to spread."

Justin Harbottle, a health promotion specialist at the Terrence Higgins Trust, said: "However good the sex is, it's not worth contracting a long-term condition.

"Gay men today have more opportunities to meet for sex than ever before.

"Part of the problem is that communication on dating apps can be brief, making it easy to cut corners on important discussions like safe sex."

He said condoms were still the best defence against infection.

Grindr told the BBC: "Grindr is highly committed to promoting safe sex within the community and strongly encourages our users to engage in safe sex practices, get tested and know their HIV status."

It added that it collaborated with a range of organisations to raise awareness about safe sex.