Need to talk? Call 1800 882 436.
It's a free call with a maternal child health nurse. *call charges may apply from your mobile

Is it an emergency? Dial 000
If you need urgent medical help, call triple zero immediately.

beginning of content

STIs and pregnancy

5-minute read

What is an STI?

Sexually transmitted infections (STIs) are infections that can be passed on during sex, and in some cases can be passed from mother to child. If left untreated, STIs can cause serious problems for both mother and child. If you think you may have an STI, it’s important to see a doctor.

STIs are caused by micro-organisms such as bacteria, viruses and parasites, and are sometimes called sexually transmitted diseases (STDs). These organisms can pass between people in semen, blood or vaginal and other bodily fluids.

Many STIs can also be transmitted by close skin-to-skin contact (for example during foreplay), through blood-to-blood contact, and by sharing needles and other equipment for intravenous drug use.

STIs can also be passed from a woman to her baby during pregnancy and childbirth.

What are the different types of STIs?

There are many different types of STIs. The most common STIs in Australia are:

There are also other infections that, while not strictly classified as STIs, are sometimes linked with sexual activity, such as:

  • hepatitis A (a viral infection)
  • thrush (a fungal infection)
  • bacterial vaginosis (an imbalance of bacteria in the vagina)
  • pubic lice or crabs (a parasite)
  • scabies (a parasite)
  • lymphogranuloma venereum (a bacterial infection)
  • mycoplasma genitalium (a bacterial infection)

What are the symptoms of STIs?

Many people with STIs have no symptoms. They may not know about it until it causes complications or a partner is diagnosed.

Other people get symptoms such as:

  • sores or bumps on the genitals, mouth or rectal area
  • pain when urinating
  • unusual discharge from the penis or vagina
  • unusual vaginal bleeding
  • pain during sex
  • sore, swollen lymph nodes, especially in the groin
  • pain in the lower abdomen
  • rash on the body, hands or feet

If you have one or more of these symptoms it doesn’t necessarily mean you have an STI, but it would be wise to see your doctor for a check-up.

Can having an STI affect my pregnancy?

STIs can affect your ability to become pregnant (your fertility), as well as your pregnancy. Women who are pregnant can get the same STIs as women who are not pregnant. If you get infected with an STI while pregnant, it can cause serious problems for you and your developing baby.

If you are pregnant, or wanting to become pregnant, it is recommended that you are tested for STIs even if you have been tested in the past. If you have concerns about this, discuss them with your doctor.

If you do contract an STI while pregnant, getting early treatment can reduce the risks. Even if the STI can’t be cured, there are things that can be done to protect you and your baby.

How can STIs affect my baby?

Some STIs, such as syphilis and HIV, can infect a baby while it’s still in the mother’s womb. Others, such as chlamydia and genital herpes, can infect the baby as it is being delivered.

STIs can pose significant health risks to unborn babies. These include:

Getting regular medical care during your pregnancy and discussing any concerns you may have of STIs with your doctor or midwife help reduce the risk of any problems caused by STIs during your pregnancy.

How are STIs diagnosed and treated?

Untreated STIs stay active in the body and may be passed on to sexual partners, or your baby, without you being aware. Therefore, it’s important to get tested if you think you may have an STI.

Having a test for STIs is simple. The type of test depends on the STI, but tests usually involve a providing a urine sample, a swab, a blood test, or a physical examination.

If the test shows you have an STI, you may need further tests and treatment. STIs caused by bacteria, like chlamydia, can usually be treated with antibiotics. Other STIs, such as those caused by viruses (for example herpes), can be managed to control symptoms, but are not always curable.

Tips for avoiding STIs

Other than not having sex with a partner that could potentially have an STI, condoms (used during penetrative sex) and dental dams (used during oral sex) offer the best protection from STIs.

Other ways to avoid STIs are:

  • staying with one uninfected partner or not having many sexual partners
  • avoiding sex with a new partner until you’ve both been tested for STIs
  • getting vaccinated against HPV and hepatitis
  • getting circumcised (if you are a man)
  • not taking drugs or drinking excessive alcohol (often associated with risk-taking behaviour)

Learn more here about the development and quality assurance of healthdirect content.

Last reviewed: December 2020


Back To Top

Need more information?

Chlamydia - MyDr.com.au

Chlamydia is a sexually transmitted infection (STI). It affects both men and women, and it's spread by having sex with a person who has the infection.

Read more on myDr website

Genital herpes

Genital herpes is a sexually transmitted infection (STI) which shows as blisters or sores on the genitals. This is caused by the herpes simplex virus (HSV).

Read more on WA Health website

The facts about Chlamydia, what it is, how to prevent it, and how to treat it

Chlamydia is on the rise in Australia and it’s the most important thing for young people to test for. It often doesn’t have any symptoms which means that it’s easy to miss without regular STI testing.

Read more on NSW Health website

Trichomonas | Family Planning NSW

Trichomonas (commonly known as ‘trike') is a sexually transmitted infection (STI) caused by a parasite. It can cause infection of the vagina or cervix (neck of the womb) in women and the urethra (urine passage) in both women and men. Trichomonas is one of the most common STIs in some parts of the world but it is not as common in Australia.

Read more on Family Planning Australia website

Genital Herpes | Family Planning NSW

Genital herpes is a common sexually transmitted infection (STI) caused by the herpes simplex virus (HSV). There are two types of herpes simplex virus.

Read more on Family Planning Australia website

Gonorrhoea | Family Planning NSW

Gonorrhoea is a bacterial sexually transmitted infection (STI). It is spread through vaginal, anal or oral sex, or by the fingers and hands from the genitals to the eyes. It is less common in the general community than other STIs such as chlamydia. Gonorrhoea can infect the throat, rectum (back passage), urethra (urine passage), cervix (neck of the womb) and eyes.

Read more on Family Planning Australia website

Gonorrhoea | Body Talk

Gonorrhoea is a bacterial STI that can infect the reproductive organs in girls and guys. Find out all the facts here as well as tips on how to stay safe.

Read more on Body Talk website

Genital Herpes (HSV) | Body Talk

Genital herpes is a common STI caused by the Herpes Simplex Virus (HSV). Find out all the facts about Genital Herpes here.

Read more on Body Talk website

Syphilis | Body Talk

Syphilis is a bacterial STI that can infect both girls and guys. Find out all the facts about Syphilis here as well as tips to keep you safe.

Read more on Body Talk website

Sexually transmitted infections (STIs) | Your Fertility

Sexually transmitted infections (STIs) are common

Read more on Your Fertility website

Call us and speak to a Maternal Child Health Nurse for personal advice and guidance.

Need further advice or guidance from our maternal child health nurses?

Healthdirect Australia acknowledges the Traditional Owners of Country throughout Australia and their continuing connection to land, sea and community. We pay our respects to the Traditional Owners and to Elders both past and present.

This information is for your general information and use only and is not intended to be used as medical advice and should not be used to diagnose, treat, cure or prevent any medical condition, nor should it be used for therapeutic purposes.

The information is not a substitute for independent professional advice and should not be used as an alternative to professional health care. If you have a particular medical problem, please consult a healthcare professional.

Except as permitted under the Copyright Act 1968, this publication or any part of it may not be reproduced, altered, adapted, stored and/or distributed in any form or by any means without the prior written permission of Healthdirect Australia.