If you are asking “how long after sex should I get tested”, the usual answer is to wait around two weeks for chlamydia and gonorrhoea, and at least four weeks for HIV and syphilis. Some sexually transmitted infections need longer before they can be reliably detected, so a repeat test may be advised.
Broadgate GP provides confidential sexual health advice and STI testing at our private GP clinic in Central London. This guide explains the main testing windows, when to seek help sooner, and how often to arrange sexual health screening.
Timing your STI test after sex
The waiting time before an STI test can detect an infection is called the window period. Testing during the early stages after sexual contact can sometimes give a false negative result, because the infection or immune response has not yet reached a detectable level.
Most common infections can be checked two to four weeks after exposure. If you have had unprotected sex, oral sex, a condom has broken, or a sexual partner has told you they may have an infection, it is sensible to speak to a healthcare professional about the most appropriate timing. You do not need to know which test you need before contacting a sexual health clinic.
If HIV exposure may have happened within the last 72 hours, seek urgent medical advice straight away. Post-exposure prophylaxis, known as PEP, may be considered after a possible HIV exposure, but it must be started quickly. Broadgate GP also provides more detailed guidance on private HIV testing and timing.
STI testing windows by infection
Different infections have different testing windows. The table below gives general guidance, but your doctor or healthcare professional may recommend testing sooner if you have symptoms, or repeating a test later if there has been a recent potential exposure.
| Infection | Usual earliest testing time after exposure | Common test type |
| Chlamydia | Around 2 weeks | Urine or swab test |
| Gonorrhoea | Around 2 weeks | Urine or swab test |
| HIV | Often 4 to 6 weeks, depending on the test | Blood tests or blood sample |
| Syphilis | Often from 4 weeks, with repeat testing sometimes needed at 12 weeks | Blood tests |
| Genital herpes | Swab if sores are present, antibody testing may take 1 to 3 months | Swab test or blood test |
| Hepatitis B and C | Usually around 12 weeks, with follow-up sometimes advised | Blood tests |
Testing too early does not mean a result is useless, but it may not be the final answer. For example, chlamydia and gonorrhoea testing at two weeks is usually more accurate than testing at four or five days. HIV test results vary depending on the type of test used: some can detect infection earlier, while standard antibody tests may take longer. Syphilis, exposure hepatitis B and exposure hepatitis C may also require follow-up, particularly if the first test was close to the exposure.
Testing after unprotected sex or a new partner
Unprotected sex increases the chance of sexually transmitted infections, but STIs can also pass through sexual contact even when a condom is used, especially infections spread by skin-to-skin contact around the genitals. Many STIs do not cause noticeable symptoms at first, so feeling well does not rule out infection.
A good practical approach is to arrange STI testing about two weeks after sex for chlamydia and gonorrhoea, then follow your clinician’s advice about HIV, syphilis and hepatitis testing. If you are entering a new relationship, both partners may choose sexual health screening before stopping condom use. In a monogamous relationship, testing may still be appropriate if either partner has had previous partners and has not had a recent screen.
If you change partners, have multiple sexual partners, or are sexually active with partners whose STI status is unknown, regular testing is sensible. Many sexual health services recommend testing every three months for people at higher risk, and at least annually for others who are sexually active. A local sexual health clinic or private sexual health clinic can advise based on your circumstances.
Symptoms that should not wait
Do not wait for the full window period if you experience symptoms after sex. You can speak to a doctor or sexual health clinic promptly, even if a repeat test may be needed later.
Symptoms that may need assessment include unusual discharge, pain when you pee, sores, blisters, a rash, pelvic or testicular pain, bleeding after sex, or itching and irritation around the genitals. These symptoms do not always mean you have an STI. A urinary tract infection, thrush, bacterial vaginosis, skin irritation and other conditions can cause similar symptoms, so professional assessment can help identify the right next step.
Some sexually transmitted infections can also be present without symptoms. Chlamydia, gonorrhoea, HIV and syphilis may not be obvious in the early stages, and symptoms can sometimes settle even while infection remains present. If you test positive, treatment and partner notification can be discussed in confidence.
Choosing the right sexual health tests
The right STI test depends on the type of sex, your symptoms, your partners and the timing of the exposure. For example, testing after oral sex may involve throat swabs as well as urine or genital swabs. If there are sores, a swab from the affected area may be more useful than waiting for an antibody test. Blood tests are used for infections such as HIV, syphilis and hepatitis.
During regular sexual health screening, many people choose to test for common STIs such as chlamydia, gonorrhoea, HIV and syphilis. Depending on symptoms and risk, your doctor may also discuss herpes simplex, trichomoniasis, hepatitis B, hepatitis C and other sexually transmitted infections. If a sexual partner has been diagnosed with a specific infection, tell your clinician so they can recommend testing and treatment where clinically appropriate.
If you are pregnant, planning pregnancy, or preparing for IVF, STI testing may be recommended because some infections can affect pregnancy or be passed to a baby. Your doctor can explain which tests are appropriate and what to do if an infection is detected.
Confidential STI testing at Broadgate GP
Broadgate GP offers private sexual health appointments and STI testing at our Central London clinic near Liverpool Street. Our service is discreet, non-judgemental and doctor-led, so you can discuss symptoms, recent sex, unprotected sex, a new sexual partner or a new relationship in confidence.
We can advise on suitable STI testing, explain the relevant window period, and discuss treatment if needed. If your test is too soon after exposure, we may recommend waiting or arranging repeat testing so the result is as accurate as possible. To arrange confidential sexual health support, contact Broadgate GP or make an appointment with our private GP team.
FAQs
Is 7 days after sex too early to test for STIs?
Seven days after sex can be too early for some STI tests. Chlamydia and gonorrhoea are usually checked around two weeks after exposure, while HIV, syphilis and hepatitis often need longer. If you have symptoms, seek advice promptly rather than waiting.
Is 2 weeks enough time to test for STDs?
Two weeks is often enough time to test for chlamydia and gonorrhoea, but it may be too early for a final result for HIV, syphilis, hepatitis B, hepatitis C or herpes antibody testing. A healthcare professional may recommend repeat testing depending on the exposure.
What STD shows up in 2 days?
Most sexually transmitted infections are not reliably detected after only two days. Some symptoms, such as irritation, sores or discharge, can appear quickly, but a test at this stage may give a false negative. If symptoms appear, speak to a doctor or sexual health clinic.
Should I get tested after every new sexual partner?
Testing after a new sexual partner can be sensible, especially after unprotected sex or if you do not know a partner’s STI status. Some people also choose screening before entering a new relationship or before stopping condom use.
How quickly can oral sex-related STIs be detected?
The timing depends on the infection and the type of test. Chlamydia and gonorrhoea affecting the throat are often tested around two weeks after exposure, using a throat swab where appropriate. HIV, syphilis and hepatitis may need blood tests at a later window period.
Can Broadgate GP help if I am unsure which STI test I need?
Yes. At Broadgate GP, a doctor can discuss your symptoms, timing, sexual contact and concerns before advising which STI tests are appropriate. You do not need to choose the tests yourself before your appointment.
