Sexually transmitted infections (STIs) can affect anyone who is sexually active. Some cause symptoms that are quickly identifiable, but many can develop with no apparent sign at all.
The absence of pain, unusual discharge, or a genital lesion does not, therefore, rule out an STI.
Screening allows an infection to be diagnosed earlier, its management to be organised, and its transmission to partners to be limited.
What is a sexually transmitted infection?
An STI is an infection that can be transmitted during sexual activity, notably vaginal, anal, or oral.
They can be caused by bacteria, viruses, or parasites.
Among the best-known STIs are notably:
- infection with Chlamydia trachomatis;
- gonorrhoea, caused by Neisseria gonorrhoeae;
- syphilis;
- HIV infection;
- hepatitis B;
- genital herpes;
- human papillomavirus (HPV) infections;
- trichomoniasis.
Not all of them are screened for in the same way, and there is no single test that can rule out every STI.
Can you have an STI with no symptoms at all?
Yes. This is even common.
The World Health Organization highlights that STIs are often asymptomatic and that, when symptoms do occur, they can be non-specific.
A person can therefore be infected, show no particular sign, and still transmit the infection.
This is notably one of the reasons why screening should not be reserved for people who have symptoms.
What symptoms might suggest an STI in women?
Depending on the infection, possible manifestations can include:
- unusual vaginal discharge;
- burning on urination;
- pelvic pain;
- pain during sexual intercourse;
- unusual bleeding or bleeding after intercourse;
- lesions, blisters, ulcers, or genital warts;
- itching or irritation;
- sometimes fever or a general feeling of being unwell.
These symptoms are not specific to STIs. They can have many other gynaecological causes.
Conversely, their absence does not rule out an infection.
A consultation therefore allows the appropriate tests to be determined.
When should you get tested?
Testing can notably be relevant:
- after unprotected or poorly protected intercourse;
- in the event of condom failure or incorrect use;
- when a partner has received an STI diagnosis;
- in the presence of symptoms consistent with an STI;
- when changing partners or having new partners;
- before considering stopping condom use within a relationship;
- when a healthcare professional recommends it based on your individual situation;
- in certain situations involving pregnancy or pregnancy plans.
The choice of infections to test for, and the timing of the test, depend on the exposure, the infection being sought, and the type of test used.
How long after at-risk intercourse should an STI test be done?
There is no single delay valid for all STIs.
Each infection has its own period during which a test can become informative. The delay also depends on the diagnostic technique used.
After a recent exposure, it may therefore be necessary to carry out an initial assessment and then, depending on the situation, repeat certain tests.
When there has been a recent potentially at-risk exposure to HIV, you should not wait for the end of a "screening window" before seeking advice: post-exposure treatment may be indicated in certain situations and must be assessed promptly.
What tests can screen for an STI?
Screening depends on the infection being sought and the exposure.
It can include:
- a blood test;
- a vaginal sample;
- a urine sample;
- depending on sexual practices and exposure, a throat or anal sample;
- a direct sample from a lesion when specific symptoms are present.
A simple blood panel therefore cannot screen for every STI.
For chlamydia and gonorrhoea, nucleic acid amplification techniques are notably used on samples suited to the exposed site.
Is a blood test enough to screen for every STI?
No.
Certain infections, such as HIV, syphilis, or hepatitis B, can notably be screened for with blood tests.
However, testing for Chlamydia trachomatis or Neisseria gonorrhoeae generally relies on appropriate samples.
The site of the sample also matters: depending on sexual practices, an infection can be present at the genital, anal, or throat level.
This is why the choice of sample must match the individual situation.
Can you get STI screening without a prescription in France?
Yes.
The French service Mon test IST allows you to request, directly at a medical biology laboratory, without a prescription and without an appointment, screening for five infections:
- HIV;
- hepatitis B;
- syphilis;
- gonorrhoea;
- chlamydia.
A questionnaire is used to determine which infections to test for and which samples are appropriate.
For people under 26, screening for these five STIs is covered at 100% by the Assurance Maladie, according to the rules of the service.
After 26, HIV screening remains covered at 100%. The other four screenings are covered at 60% by the Assurance Maladie, with the remainder potentially covered by supplementary health insurance depending on the situation.
Reimbursement arrangements may change: it is useful to check the Assurance Maladie's up-to-date information.
Can you get an STI test free of charge and anonymously?
Free STI, HIV, and hepatitis screening and diagnosis centres (CeGIDD) are another option.
They carry out prevention, screening, diagnosis, and outpatient management of STIs.
People who wish to benefit from free and anonymous testing can notably turn to a CeGIDD.
Is there an at-home STI screening option?
Yes, in certain situations.
In France, the Assurance Maladie offers, in 2026, an at-home self-sampling kit for eligible people aged 18 to 25.
This kit screens for two bacterial infections:
- Chlamydia trachomatis;
- Neisseria gonorrhoeae.
It is therefore not a complete screening for every STI.
Is HPV included in Mon test IST?
No.
Human papillomaviruses (HPV) are not among the five infections tested for in the Mon test IST laboratory service.
Cervical cancer screening follows a specific strategy, according to age and national recommendations.
STI screening should therefore not be confused with cervical cancer screening.
Is genital herpes tested for in a standard STI panel?
Not systematically.
In the presence of blisters, ulcers, or other suggestive lesions, clinical examination and, where indicated, a sample from the lesion can help with diagnosis.
Herpes is not among the five infections tested for by Mon test IST.
Chlamydia: why is screening particularly important?
Chlamydia trachomatis infection can be silent.
When it is not diagnosed and treated, it can, in certain situations, be associated with upper genital tract complications and have consequences for reproductive health.
Appropriate screening allows the infection to be diagnosed and treatment to be offered when necessary.
What about gonorrhoea?
Gonorrhoea can also be asymptomatic.
Its diagnosis relies on samples suited to the exposed sites.
Antibiotic resistance is a particularly important issue: the WHO highlights the increase in resistance of Neisseria gonorrhoeae, which is why treatment recommendations must be followed and self-medication with antibiotics avoided.
What should you do if an STI test is positive?
A positive result should not be experienced as a fault or a judgement on your sex life.
The appropriate course of action depends on the infection diagnosed.
It can include:
- treatment, where one exists;
- further tests;
- recommendations regarding sexual intercourse during the treatment or contagious period;
- informing, and, depending on the infection, screening or treating partners;
- a check-up after treatment in certain situations.
It is important to follow the healthcare professional's recommendations and not to take antibiotics without medical guidance.
Should you inform your partner(s)?
When an STI is diagnosed, treating partners can be important to avoid a persistent chain of transmission and the risk of reinfection.
The approach depends on the infection and the situation.
A doctor, a midwife, a CeGIDD, or another professional involved in your care can explain the appropriate steps.
Does a condom protect against every STI?
The condom is a major means of STI prevention and greatly reduces the risk of transmission when used correctly.
Protection is not, however, absolute for every infection, notably when transmission can occur through contact with areas of skin or mucous membrane that are not covered.
STI prevention therefore relies on several tools: condoms, appropriate screening, vaccination where it exists — notably against HPV and hepatitis B — and specific HIV prevention strategies depending on the situation.
STI screening and gynaecological consultation: what is the gynaecologist's role?
A gynaecological consultation can be an opportunity to talk freely about:
- at-risk intercourse;
- a new partner;
- genital symptoms;
- contraception;
- exposure to an STI;
- screening;
- vaccination against HPV or hepatitis B;
- questions about sexuality.
This information allows the tests to be tailored, without judgement and with confidentiality respected.
Key points to remember
An STI can be present with no symptoms at all.
There is no "universal test" capable of screening for every sexually transmitted infection: tests and sampling sites must be tailored to the exposure and the infections being sought.
In France, Mon test IST provides easy access, without a prescription or appointment, to screening for HIV, hepatitis B, syphilis, gonorrhoea, and chlamydia.
In the event of symptoms, recent exposure, a partner with a positive diagnosis, or doubt about the right time to test, a healthcare professional can determine the most appropriate screening strategy.
Medical information: this article provides general information and does not replace a medical consultation. In the event of significant symptoms, acute pelvic pain, pregnancy, or recent potentially at-risk exposure to HIV, prompt medical assessment may be necessary.
Medical and Institutional Sources
Assurance Maladie. Dépister les IST. Mise à jour : 4 juin 2026. https://www.ameli.fr/assure/sante/themes/mst-ist/depistage
Ministère chargé de la Santé. Renforcement de la prévention des IST : dépistage à la demande du patient et sans ordonnance. 30 août 2024. https://sante.gouv.fr/actualites/presse/communiques-de-presse/article/renforcement-de-la-prevention-des-ist-le-depistage-a-la-demande-du-patient-et
Organisation mondiale de la Santé (OMS). Infections sexuellement transmissibles (IST). Mise à jour : 10 septembre 2025. https://www.who.int/fr/news-room/fact-sheets/detail/sexually-transmitted-infections-%28stis%29
Assurance Maladie. Mon test IST : kit de dépistage à domicile. Actualisation 2026.
Consult Dr. Yasmine Maazouzi at the Hôpital Privé Beauregard (23 Rue des Linots, Bât. B5 ICOGM, Marseille 13004) for any question about STI screening.