Safer sex basics: condoms, dental dams and lubricant

Safer sex basics come down to a few habits: using a barrier such as a condom or a dental dam, using it correctly, and getting tested. This guide sets out what the NHS and the CDC say about each of them. Every source is listed at the end. It is general information, not medical advice, and it cannot speak to your own situation. For that, a doctor, a nurse or a sexual health service is the right place to ask.

What safer sex means

Safer sex means lowering the chance of catching or passing on a sexually transmitted infection (STI). The CDC writes that the only way to avoid STIs is not to have vaginal, anal or oral sex. For people who do have sex, it names two ways to lower the risk. The first is a long term, mutually monogamous relationship with a partner who does not have an STI, for example a partner with negative test results. The second is using latex condoms the right way every time.

The NHS explains why habits matter. Many STIs have no symptoms, so a person can have one without knowing it and pass it on during sex. The only way to know for sure is to get tested. The guide to STI testing covers the basics.

Barriers at a glance

Barrier	Used for	Worth knowing	Source
External condom	Vaginal, anal and oral sex	Put it on before any genital contact, and use a new one every time	NHS, CDC
Internal condom	Vaginal sex and anal sex	Helps protect against STIs when used correctly for vaginal sex. For anal sex there is not enough evidence to say how much	NHS
Dental dam	Oral sex on the vagina or anus	A thin sheet of latex or polyurethane. A condom can be cut open to make one	CDC

External condoms

The NHS says that using a condom every time you have sex is the best way to protect you and your partner from HIV and other STIs. Condoms can be used for vaginal, anal and oral sex, and some people also put one on a sex toy. Sex toy safety looks at toys in more detail.

Before you use one

• Use a new condom every time, and follow the instructions on the packet.
• Check the use by date. The NHS says an expired condom may not be effective.
• Look for a safety mark on the packet, which means the condom has been tested to high safety standards.
• Check what it is made of. Some condoms are latex and others are latex free, and the packet says which. The NHS advises against latex condoms if you have a latex allergy, or if you are using an antifungal medicine on or around the genitals or anus.
• Do not keep condoms in a wallet. The CDC says heat and friction can damage them.

Putting one on and taking it off

1. 1

   Open with care

   Open the packet carefully so you do not damage the condom. The NHS says not to use your teeth, which could rip it.

2. 2

   Put it on first

   Put it on before any genital contact, meaning before the penis touches the vagina or anus.

3. 3

   Roll it to the base

   Squeeze the air out of the tip, then roll the condom all the way down. If it will not roll down, it may be the wrong way round, and the NHS says to throw it away and use a new one.

4. 4

   Keep it on

   Keep it on until sex has finished. Grip the base as you pull out, so it stays in place.

5. 5

   Bin it

   Put a used condom in the bin, not in the toilet.

Two mistakes are worth knowing. The NHS says that using more than one condom at once can make one or both split, and the CDC says that a condom should never be reused.

Internal condoms

An internal condom is made of thin, soft plastic or rubber and goes inside the vagina or anus before sex. The NHS says that almost all are made of plastic or synthetic rubber, that some are latex, and that the packet says which.

According to the NHS, an internal condom can be inserted up to 8 hours before sex. The steps it gives are:

1. 1

   Open carefully

   Open the packet without using your teeth.

2. 2

   Insert it

   Hold the inner ring, insert the condom into the vagina and push it in as far as you can with a finger.

3. 3

   Keep the ring out

   The outer ring stays outside the vagina, and during sex the penis goes inside the condom.

4. 4

   Remove it with care

   Afterwards, twist the outer ring a few times so that semen does not leak out as you remove it, and put the condom in the bin, not the toilet.

Do not use an internal condom together with an external condom: the NHS says one or both can split. It also gives examples of incorrect use: inserting the condom after the penis has touched the vagina, letting it split or move out of place, and the penis entering the vagina outside the condom.

On protection, the NHS says that internal condoms help protect against STIs when used correctly for vaginal sex. For anal sex they may help, but there is not enough evidence to say how much protection they offer.

Dental dams

The CDC describes dental dams as latex or polyurethane sheets used between the mouth and the vagina or anus during oral sex. Ready to use dams can be bought online, and the CDC explains how to make one from a latex or polyurethane condom: cut off the tip and the base, cut down one side and lay it flat.

The CDC’s advice for dental dams:

• Use a new dental dam every time you have oral sex.
• Read the packet, check the expiry date and check for tears or defects.
• Put it in place before you start and keep it on until you finish.
• Store it in a cool, dry place.
• Do not reuse it, do not stretch it and do not flush it down the toilet.

Lubricant and latex

The NHS says not to use oil based lubricant with latex condoms, and the same goes for internal condoms made of latex. Water based or silicone based lubricant is the alternative it names. The CDC lists baby oil, lotion, petroleum jelly and cooking oil among the products that will make a condom or a dental dam break, and it advises water based or silicone based lubricant with dental dams to prevent breakage.

Oral sex

The CDC says that many STIs spread through oral sex. It lists chlamydia, gonorrhoea, syphilis, herpes, HPV and HIV, and writes that anyone exposed to an infected partner can get an STI in the mouth, throat, genitals or rectum. It adds that many STIs have no symptoms, so they can be passed on even when nobody has any signs.

On HIV, the CDC says the risk of getting or passing it on through oral sex is little to none, and that studies show it is much lower than through vaginal or anal sex. It notes that this may not be true for other STIs.

Using a condom, a dental dam or another barrier every time can reduce the risk of giving or getting an STI. For oral sex on the penis, the CDC suggests a latex condom without lubricant, or a polyurethane one if you or your partner is allergic to latex. For oral sex on the vagina or anus, it suggests a dental dam, or a condom cut open to make a square and placed between the mouth and the vagina or anus.

If a condom splits or comes off

The NHS gives urgent advice here. Get urgent help from a pharmacist, a sexual health clinic or a doctor if a condom splits or comes off during sex, or if an internal condom splits, moves out of place or leaks. You may need emergency contraception or an STI test.

Testing and talking

The CDC says that if you are having sex, you should ask your healthcare provider to test you regularly for STIs and HIV. It also advises talking openly with the provider about activities that might put you at risk, including oral sex, and talking to your partners about STIs. The NHS adds that doctors and healthcare professionals are there to help, so try not to feel uncomfortable about sharing information about your sexual activities or sexuality. The kink negotiation checklist includes a health and safety section, and talking about desire offers gentle ways to start a conversation. For the cervix, cervical screening and HPV explains the smear test, and cystitis and UTIs has its own guide.

All of this assumes that everyone involved has agreed. What sexual consent is sets out how consent works.

When to get help

The NHS advises going to a sexual health clinic if:

• You think you may have an STI.
• A sexual partner has symptoms of an STI.
• You are worried after having sex without a condom or dental dam.
• Symptoms of an STI during pregnancy.
• You are having sex with new partners.

It adds that you should not have sex, including oral sex, without a condom or dental dam until you have had a checkup or been tested. The section on what a test involves in the STI testing guide explains what a visit looks like.

Questions about safer sex

Do I need a barrier for oral sex?

The CDC says that many STIs spread through oral sex and that using a condom, a dental dam or another barrier every time can reduce the risk. It says the risk of HIV from oral sex is little to none, but that this may not be true for other STIs.

Which lubricant goes with condoms?

The NHS names water based or silicone based lubricant for latex condoms and advises against oil based ones. The CDC adds that baby oil, lotion, petroleum jelly and cooking oil will make a condom or a dental dam break.

Can I make a dental dam from a condom?

The CDC describes how: open and unroll a latex or polyurethane condom, cut off the tip and the base, cut down one side and lay it flat.

What if I am allergic to latex?

The NHS says not to use latex condoms if you have a latex allergy, and notes that some condoms are latex free, which the packet will say. The CDC suggests polyurethane condoms for oral sex on the penis if you or your partner is allergic to latex.

Can I use two condoms to be safer?

No. The NHS says that using more than one condom at a time can make one or both split. It gives the same warning about using an internal condom together with an external one.

What should I do if a condom splits?

The NHS advises getting urgent help from a pharmacist, a sexual health clinic or a doctor. You may need emergency contraception or an STI test.