Prostitutes and escort agencies have created hundreds of unrestricted pages on Facebook.
This has sparked concern that children are being exposed to both explicit content as well as the services of the sex industry, the Telegraph reports.
Many of the pages include explicit photographs, descriptions of services alongside phones numbers, addresses and prices.
Facebook has removed dozens of the pages after being contacted by The Times newspaper.
The site said it “has a clear set of rules and these pages broke them”, but said it could only take action when offensive items were reported to them by members of the public.
According to the paper, the postings were also reported to Twitter, but the microblogging site declined to comment or take action.
Under the company’s rules, content would need to be illegal to be considered in breach of its terms and conditions, the paper added.