The number of sexually transmitted infections continues to rise, figures suggest.
Chlamydia is the most common STI
The Health Protection Agency revealed diagnoses of sex infections rose by 3% to 790,387 from 2004 to 2005.
The biggest rise was seen in syphilis cases, which rocketed by 23% to 2,807, but Chlamydia, genital warts and herpes also registered increases.
New cases of gonorrhoea bucked the trend by falling by 13% - a substantial drop for the second successive year.
Sexual infection diagnoses have been almost continually rising since the 1990s, with the highest increases in recent years being seen in the 16 to 24 age group.
HPA infections expert Professor Peter Borriello said the figures contained "mixed news" with the fall in gonorrhoea showing real progress was being made.
"However, it is disappointing to see that there was a further rise in new diagnoses of STIs and these figures show there is still much to be done to tackle the continuing spread of infection."
He said some of the rise could be accounted by better testing arrangements being put in place by sexual health clinics.
But he added: "Today's figures serve as a reminder for people to take responsibility for their own sexual health and that of their partners and to use a condom with new and casual partners."
The rise in syphilis diagnoses from 2,278 to 2,807 was a smaller increase than the previous year. New cases were particularly marked among women with the rate over two times higher than for men.
Chlamydia remains the most commonly diagnosed STI with 109,832 new cases in 2005 - a 5% increase on the previous year.
Genital warts increased by 1% to over 81,000 cases, while genital herpes rose by 4% to nearly 20,000 cases.
The number of gonorrhoea diagnoses fell from 22,350 to 19,495.
Nick Partridge, chief executive of the Terrence Higgins Trust, said: "The government has prioritised sexual health and there now needs to be action locally.
"Getting an appointment at a sexual health clinic must be quick and easy, treatment must be swift and we need to keep pushing home the safer sex message - it's more important than ever."
Jan Barlow, chief executive of Brook, the sexual health charity for young people, said the rises were being compounded by the deficits problem gripping the NHS.
"Iin some areas facing financial pressures, money earmarked for sexual health services has apparently been diverted to help balance the books."
A Department of Health spokeswoman said the government was committed to improving sexual health services as proved by the extra £300m being invested in coming years.
But she added: "People need to realise that if they don't protect themselves they could end up with a serious STI that could affect their long term health."
Meanwhile, the government released data showing the number of abortions rose slightly by 0.4% last year to 186,400 terminations in England and Wales.