Getting pregnant and sexually transmitted infections (STIs)

Why is it important to have a sexual health check-up before trying to get pregnant?

Sexually transmitted infections (STIs) are passed from 1 person to another through genital contact or unprotected sex. This includes vaginal, anal and oral sex, genital touching or sharing sex toys.

It does not matter how many times you’ve had a sexual experience or how many people you have had sex with, if 1 sexual partner has an infection you may catch it.  

It is a good idea to get checked (and treated if needed) for an STI before you get pregnant because:

• some STIs can affect female fertility and male fertility, making it difficult to get pregnant
• some STIs can cause health problems for you and your baby during and after pregnancy
• some treatments for STIs are not suitable if you are pregnant.
• you will not be offered tests for all STIs during pregnancy.

Any sexual partners you have while trying to get pregnant or during pregnancy should also get tested.  

What are the symptoms of a sexually transmitted infection (STI)?

A person can have an STI without showing any symptoms, which is why STIs can spread easily.

If you do have symptoms, they may include:

• unusual discharge from the vagina, penis or anus (bottom)
• pain when weeing (passing urine)
• lumps or skin growths around the genitals or anus
• a rash
• unusual vaginal bleeding
• itchy genitals or anus
• blisters and sores around the genitals or anus
• warts around your genitals or anus
• warts in your mouth or throat.

Chlamydia 

Chlamydia is 1 of the most common STIs in the UK and does not usually cause any symptoms. If left untreated, chlamydia can cause:

• male and female infertility  
• pelvic inflammatory disease  
• ectopic pregnancy.

If you have chlamydia that is not treated in pregnancy this can cause premature labour and birth or your baby being born with a low birth weight.

It is also possible to pass the infection to your baby. This can cause:

• an eye infection
• a lung infection.

Chlamydia can usually be effectively treated with antibiotics.

Gonorrhoea

Gonorrhoea is 1 of the most common STIs in the UK.

If left untreated, chlamydia can cause:

• female infertility (difficulty getting pregnant)
• pelvic inflammatory disease  
• reduced fertility in men
• ectopic pregnancy.

During pregnancy, gonorrhoea can cause:

• miscarriage
• premature labour and birth
• the baby being born with conjunctivitis.

Gonorrhoea is usually treated with antibiotics. If treated early, gonorrhoea is unlikely to lead to any complications or long-term problems.  

Genital herpes  

Genital herpes is an STI that can cause small blisters on your genitals, anus, thighs or bottom. Herpes symptoms might not appear for weeks or even years after you're infected with the virus. Many people have no symptoms at all.

Once you have the genital herpes virus, it stays in your body. There is no cure for genital herpes, but treatment can help manage the symptoms.  

If you have genital herpes during pregnancy, there's a small risk your baby could develop a serious illness called neonatal herpes. This can cause death, but most babies recover with antiviral treatment.

If you are diagnosed with genital herpes before you get pregnant, your GP (then a midwife) can help you manage the condition and reduce the risks. Treatment for genital herpes is safe to take during pregnancy.

Genital warts

Genital warts are caused by a virus called human papillomavirus (HPV). There are many types of HPV. We have more information about HPV.

During pregnancy, genital warts:

• can grow and multiply
• become irritated easily
• may be passed to the baby during birth, but this is rare.  

Genital warts can be treated in pregnancy, but not all treatments are suitable. Genital warts often disappear on their own within 6 weeks after the baby is born, so treatment is often delayed until after the birth. Your GP and midwife can help you manage any symptoms.

Syphilis

Syphilis is a bacterial infection that can cause serious long-term health problems , if left untreated. It can be cured with antibiotics.  

If you're pregnant and have syphilis, you can pass it on to your baby before they're born. This is known as congenital syphilis.  

Having syphilis during pregnancy can also cause:

• miscarriage
• stillbirth
• premature birth.

All pregnant women are offered a test for syphilis during pregnancy so the infection can be found and treated safely.  

HIV 

HIV (human immunodeficiency virus) is a virus that damages the cells in your immune system making it harder for your body to fight everyday infections and disease. HIV cannot be cured but there is medicine to manage it. Treatment can also prevent you passing it on, which means you won’t infect anyone else.

HIV treatment can also prevent you passing HIV to your unborn baby. Without treatment, there's a 1 in 4 chance your baby will become infected with HIV. With treatment, the risk is less than 1 in 100 (less than 1%)

Your HIV doctor or a nurse can give you specialist advice about getting pregnant safely. We have more information about planning a pregnancy with HIV.  

Where can I go for a sexual health check-up? 

The best places to go are a genito-urinary medicine (GUM) clinic, sexual health clinic, your GP or a young people’s clinic.

All information given will be kept confidential, and the tests are only done with your permission.

Find a sexual health clinic in England.  
Find a sexual health clinic in Wales. 
Find a sexual health clinic in Northern Ireland. 
Find a sexual health clinic in Scotland.

Remember that any partners you have while you are trying to get pregnant should have a sexual health check-up too.

What if I find out I have an STI?

Try not to worry because most STIs can be treated. Just be aware that some treatments are not suitable if you are trying to get pregnant. Your GP, pharmacist or clinic will let you know which ones.

If you have an STI you shouldn’t have sex until you and any partners have completed treatment and the infection has cleared. Sometimes, symptoms may not go away after the first treatment and you may need another round. If the treatment doesn’t work you may need more tests.

Tell the doctor, nurse or pharmacist that you want to start trying to get pregnant. They can give you more advice about when the infection should clear and when you can start trying for a baby again.

What if I have an STI that can’t be cured?

It can be a very anxious time if you find out you have a STI that can’t be cured. But if the infection is treated and managed well, you can get pregnant safely and have a healthy baby.

Talk to your doctor or nurse. It’s important to understand your condition and what you need to do to stay healthy and get pregnant safely.

It’s also important to tell your midwife about your condition at your booking appointment. They can help you manage your symptoms during pregnancy.  

Always check with your doctor or nurse that it’s okay to take any medications you are prescribed while you are trying to get pregnant.

Remember that even if you or any partners have no STIs when you get pregnant, it’s still a good idea to practice safe sex through your pregnancy.

More support and information

Brook the young people's sexual health charity for under-25s provides advice, support and information about your nearest sexual health clinic.

The Family Planning Association (FPA) provides information about STIs, pregnancy choices, abortion and planning a pregnancy.

Terrence Higgins Trust provides information, support and advice about HIV and sexual health.  

i-base provides information about HIV including pregnancy and women’s health