Sexually transmitted infections

Sexually transmitted Infections

Sexually transmitted infections (STIs), are infections that are passed from one person to another by sexual intercourse. They do not always produce obvious symptoms and can produce long term complications such as pelvic pain, chronic cystitis, infertility or abnormalities of the cervix.

The commonest STIs are:


  • Chlamydia
  • Genital Warts (HPV)
  • Genital Herpes
  • Gonorrhoea
  • HIV and AIDS


Chlamydia is the commonest STI in the UK.  In women it can cause:

  • Pain passing urine/cystitis
  • Vaginal discharge
  • Pelvic pain
  • Pain during or after sex
  • Bleeding between periods
  • Heavy periods


Chlamydia can be diagnosed with a vaginal or cervical swab, or urine testing.

It is treated with antibiotics but if left undetected and untreated, it can lead to long term problems such as infertility.


Genital Warts (HPV)


Warts are are the second most common STI in England after Chlamydia and are caused by the human papilloma virus (HPV). They look like small fleshy growths, bumps or skin changes on or around the genital or anal area.

Warts are usually painless, but can cause itching, redness or bleeding.

HPV is spread by skin-to-skin contact so can be transmitted without penetration.

Several treatments are available for genital warts, including creams and freezing the warts (cryotherapy).


Genital Herpes


Herpes is a common infection and is caused by the herpes simplex virus, which is the same virus that causes cold sores.

It appears as small, painful blisters, which may be itchy, and cause pain passing urine.

This is typically treated with antiviral medication.




Gonorrhoea is passed to another during sexual intercourse. Half of women who contract this infection may have no symptoms at all.

Symptoms if they do occur include pain passing urine, a yellow or green vaginal discharge, pelvic pain, bleeding after sexual intercourse, bleeding between periods, or occasionally heavy periods.

Gonorrhoea can also affect other parts of a woman’s body including the rectum, eyes or throat.

It is detected with a swab and is treated with antibiotics but, like chlamydia, can lead to long term health problems if not detected and treated.




HIV is passed on by sexual intercourse, but can also be transmitted through exposure to infected blood such as shared needles used by drug abusers.

When HIV infection is in its final stages, it is called AIDS and represents that the immune system is weakened such that it is unable to fight infections.

When HIV is first developed it may be accompanied by a flu like illness but after this it may produce no symptoms.

A simple blood test can detected HIV infection.