Skip to main content

Sexually transmitted infections (STIs) are common. People who have an STI often have no symptoms and can therefore have the infection for some time without being diagnosed or treated. STIs like chlamydia, gonorrhoea, syphilis, and mycoplasma genitalium can cause fertility problems.

Some people with STIs don't experience any symptoms.
  • Facts about chlamydia

    Chlamydia is a very common bacterial infection that can affect anyone who has had unprotected sex. 

  • Signs and symptoms

    About 75 percent of women and 25 percent of men with chlamydia have no symptoms. As symptoms of chlamydia can be similar to those of other conditions such as thrush and cystitis, it may be overlooked.

    When symptoms of chlamydia do occur, they can include:

    For women

    • pelvic pain
    • painful and heavy periods
    • deep pain with vaginal sex
    • bleeding between periods or after having sex
    • frequent and burning urination
    • unusual vaginal discharge.


    For men

    • discharge from the penis
    • burning or pain when urinating
    • itching or irritation around the opening of the penis
    • pain or soreness in the testes.
  • How can chlamydia affect fertility?

    For women

    Chlamydia causes inflammation of the urethra (the tube from the bladder that urine is passed through) and/or the cervix (the end part of the uterus that sits in the top of the vagina).

    If left untreated the infection can travel to the uterus, fallopian tubes and ovaries. When the infection moves to these areas it is referred to as pelvic inflammatory disease (PID).

    PID can cause scarring and adhesions (bands of scar tissue) which can lead to serious health problems including chronic pelvic pain, ectopic pregnancy and fertility problems.

    Symptoms of PID include:

    • pain and tenderness in the lower abdomen
    • deep pain during sexual intercourse
    • heavy and painful periods
    • fever.


    For men

    Chlamydia causes inflammation of the urethra (the tube in the penis that urine and sperm pass thorough). If left untreated chlamydia can progress to the epididymis (the tubes that carry sperm). It can cause pain, scarring and, rarely, fertility problems.

  • How is chlamydia treated?

    Chlamydia is treated with antibiotics.

  • Facts about gonorrhoea

    Gonorrhoea is a bacterial infection that is carried in genital fluid.

    It is easily transmitted during vaginal intercourse and can also be transmitted during anal or oral sex. It usually affects the genital area, although the throat or anus may also be affected.

  • Signs and symptoms

    Women with gonorrhoea often don’t have any symptoms. This means that gonorrhoea can go undetected for a long time. Most men do experience symptoms.

    When symptoms do occur, they include:

    For women

    • An unusual discharge from the vagina
    • Pain while urinating.


    For men

    • A burning sensation while urinating
    • A white or yellow pus-like discharge from the penis.
  • How can gonorrhoea affect fertility?

    For women

    If left untreated, gonorrhoea can lead to pelvic inflammatory disease (PID), which can cause infertility.

    Symptoms of PID include:

    • lower abdominal pain and tenderness
    • deep pain during sexual intercourse
    • heavy and painful periods
    • fever.

    Women who have had PID need to be especially careful about gonorrhoea, because the risk of infertility increases with each bout of inflammation.


    For men

    Gonorrhoea can damage the epididymis (the tubes that transport sperm), which can stop sperm passing from the testes into the ejaculate.

  • How is gonorrhoea treated?

    Gonorrhoea is treated with antibiotics.

  • Facts about genital herpes

    Genital herpes is caused by the herpes simplex virus (HSV) and is transmitted through skin-to-skin contact during vaginal, anal or oral sex.

  •

    Symptoms include small, painful blisters on the genitals and a burning sensation when urinating. It is most contagious when a person has a blister or sore. Many people with HSV have no symptoms or only have minor symptoms such as an itch but they can still pass on HSV. HSV can’t be cured and symptoms will flare up from time-to-time, but there are drugs that can reduce the severity and frequency of the symptoms.

    Most women and people with uteruses who have HSV in their body can expect at least one flare-up during pregnancy. Since HSV can be transmitted to the baby through direct contact with the virus during birth, it is recommended that pregnant women and people with uteruses who have active blisters when they are close to giving birth, have a caesarean section.

  • Facts about syphilis

    Syphilis is caused by bacteria that is transmitted by direct contact during oral, vaginal or anal sex. It can be transmitted during pregnancy to the baby, which is referred to as congenital syphilis.

  •

    Congenital syphilis can result in health problems for the child at birth and later in life. Syphilis can also cause miscarriage and stillbirth. Pregnancy-related complications due to syphilis are very rare in Australia because pregnant women are tested and if they are found to have the infection they can be safely treated with antibiotics, to prevent these complications.

  • Facts about mycoplasma genitalium

    Mycoplasma genitalium is a more recently identified but increasingly common bacterial STI. It is caused by bacteria which infects the cervix, urethra and rectum.

  •

    In women and people with uteruses, it can cause vaginal discharge, inflammation in the urethra and cervix, and pelvic inflammatory disease, and can increase the risk of infertility. In some men and people with penises, the infection does not cause any symptoms but others can experience inflammation of the urethra, painful urination, and discharge from the penis. Mycoplasma genitalium can be effectively treated with antibiotics.

  • What you can do

    The earlier STIs are diagnosed and treated, the less likely they are to cause fertility problems. Having an STI test before trying for a baby reduces the risk of passing an infection on to your partner or child.

    If you have had unprotected sex, regardless of whether you have symptoms of an STI, see your doctor for a check-up. While this might be a bit awkward or embarrassing for you, STIs are very common and health professionals deal with STIs all the time.

    It is important to have regular STI tests once you become sexually active as a lot of STIs can be asymptomatic. Some STIs are treatable with antibiotics and the sooner treatment starts, the less risk of complications.

    Making STI testing a part of your regular check-ups can help you to normalise talking about sexual and reproductive health as well as ensure that STIs do not cause fertility problems later in life.

  • References
    • Hart, R. J. (2016). Physiological Aspects of Female Fertility: Role of the Environment, Modern Lifestyle, and Genetics. Physiological Reviews, 96(3), 873-909. doi: 10.1152/physrev.00023.2015

Page created on: 29/08/2018 | Last updated: 19/05/2024

Looking for more?

Image of STI fact sheet

Sexually transmitted infection and reproductive outcomes

If they are left untreated they can adversely affect male and female fertility and other reproductive outcomes...

Image of Thinking about having a baby resource

Thinking about having a baby?

What men and women can do to increase their chance of getting pregnant and having a healthy baby...

What's next?

Find out how a more healthy lifestyle increases your chance of pregnancy and having a healthy baby.

Find out more