This article was contributed by FPA

The Family Planning Association is a sexual health charity. It gives straightforward information, advice and support on sexual health, sex and relationships to everyone in the UK.

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Sexually transmitted infections: eight useful facts

Image: FPA

If your teen is having unprotected sex, they could catch an STI. Here’s what you need to know, and information on where you and your child can find help online

A sexually transmitted infection (STI) is an infection that can be passed on through unprotected sex (vaginal, oral or anal), genital contact and through sharing sex toys.

Compared to other age groups, young people aged under 25 have the highest rates of STIs in the UK so however you feel about your child becoming sexually active, if they’re having (or planning to have) sex then they need to know how to look after their health.

You can help by being there if they have questions, making sure they know the risks, and knowing where they can go for help. (To help you start that conversation, read our advice for talking about sex with your teen.)

Anyone can get an STI

STIs don’t just affect people with lots of sexual partners. Anyone who's sexually active can get an STI – even if they've only had sex once.

Using a condom is the best way to help protect against STIs

Condoms are the only method of contraception that also help protect against STIs. They won’t stop all infections (for example those passed on through skin-to-skin contact) but they are the best way to prevent most infections being passed on.

Try to make sure your child knows where they can get condoms. Sexual health clinics give them out for free and many areas run free condom distribution schemes such as C-card or Come Correct.

A dam (a square piece of latex or polyurethane) can be used as barrier between the mouth and vagina or anus during oral sex.

People of any age can struggle to talk about using condoms with their partner – your child might find this blog post from IPPF helpful when it comes to negotiating condom use.

There are more than 30 STIs

Some of the most common are:

  • Chlamydia (up to one in ten sexually active young people are thought to have this)
  • Genital warts
  • Genital herpes
  • Gonorrhoea
  • Non-specific urethritis

Less common, but not rare, are:

  • Trichomonas vaginalis
  • Pubic lice
  • Scabies
  • Syphilis
  • HIV

You can find out more about all these infections on FPA’s website.

Not everyone with an STI has signs or symptoms

Make sure your child knows that just because someone hasn’t got symptoms it doesn’t mean they’ve not got an STI. For example, around 70% of women and 50% of men with chlamydia won’t have obvious symptoms but could still pass the infection on.

If your child confides in you that they’ve had unprotected sex (without using a condom) or found out that a sexual partner has an STI then it’s definitely worth them seeking advice or having a check-up.

Most STIs are easily treated but it pays to act quickly

Most STIs can be treated and it’s usually best if treatment is started as soon as possible.

Infections such as chlamydia and gonorrhoea require antibiotics, others may need creams, lotions or other treatment. Some viruses, such as HIV, never leave the body but treatment can reduce the symptoms and help prevent or delay any complications.

If left untreated, many STIs can be painful or uncomfortable and can be passed on to someone else. Some infections, such as chlamydia and gonorrhoea can spread and cause damage to health and fertility if left untreated.

Testing is free and confidential

Your child can be tested and get treatment at a GUM (Genito-Urinary Medicine) or sexual health clinic. General practices, contraception clinics, young people’s services and some pharmacies may also provide testing for some infections.

‘All advice, information and tests from NHS services and the NCSP are free’

In England, the National Chlamydia Screening Programme (NCSP) offers testing at various locations around the country and also gives out free home testing kits from

All advice, information and tests from NHS services and the NCSP are free, but there may be a prescription charge for any treatment prescribed by a general practice.

Testing is usually quick, easy and pain-free

Young people might be reluctant to get a test because they think it will hurt or be embarrassing. If your child is worried about this, try to reassure them that health professionals deal with STIs every day and that testing is usually very easy.

The test used depends on which infections are being tested for but could involve giving a urine sample, having blood taken or taking swabs from the urethra or (for young women) the vagina. If a young person has never had a swab taken before they might be nervous about it, but although it can be uncomfortable for a moment it isn’t painful. Many services will offer young people the option of using a swab themselves.

Sometimes the results will be available straight away, and sometimes there will be a wait. The service will explain how they will get the results.

There are people who can talk to your child about STIs

However good your intentions, there are times when young people just don’t want to talk to their parents about sex. Try to make sure they know who else they can talk to, for example, a school nurse, a counsellor at college, a nurse at their general practice, staff at a clinic, another trusted adult, or a helpline or enquiry service.

Further reading

NHS sexual health information

Advice from Brook on STIs

The advice published on Parent Info is provided by independent experts in their field and not necessarily the views of Parent Zone or NCA-CEOP.

Updated: ​May 2018

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