Ordinary web users in China will be banned from surfing sex-related medical and research websites from next month, amid an Internet crackdown on pornographic online content, according to new regulations.

Medical information service providers must install software to ensure only professionals can access sites that carry information and research about sex, the regulations on the website of the Ministry of Health (www.moh.gov.cn) said.

It is prohibited to spread pornographic content in the name of sex-related scientific research, the regulations said.

But the rules risk slowing sexual health education in a country where many people are too embarrassed to talk publicly about sex.

Chat rooms on health channels in popular web sites, which are one of the few sources of information on sexuality and sexually transmitted diseases, may also be covered by the regulations.

The health sections of web portals are not allowed to conduct sex-related research services, the regulation added.

The rules do not specify exactly what is covered by scientific research into sex.

The rules come after a series of anti-porn efforts that culminated in the announcement earlier this month that Beijing would demand the installation of Green Dam Internet filtering software on all new personal computers manufactured or shipped after July 1.

Beijing says the programme will protect children from pornographic and violent information, but critics fear it is a pretext for a wider crackdown on groups and sites the government fears or disapproves of, in a year of sensitive anniversaries.

(Reporting by Beijing newsroom; Editing by Ken Wills)