STI Screening: Why It Matters and What to Expect

I believe STI screening should be a normal, non-judgmental part of gynaecological care. Sexually transmitted infections remain remarkably common in the UK, with rates of chlamydia, gonorrhoea, and syphilis all continuing to rise in recent years. Despite this, many women feel uncomfortable discussing sexual health or are unsure when screening is appropriate. In my clinic, I see this hesitation regularly — intelligent, health-conscious women who have simply never been offered a straightforward conversation about STI testing. In France, where I trained, sexual health screening is integrated into routine gynaecology visits. It is treated as a standard component of preventive care, not something separate or stigmatised. I have carried that approach into my London practice, and I believe the UK would benefit from adopting a similar attitude.

A cultural comparison: French vs UK attitudes to sexual health

Having practised in both France and the United Kingdom, I have observed a meaningful difference in how sexual health is approached. In France, gynaecologists are the primary providers of sexual and reproductive healthcare. STI screening, contraception, cervical screening, and general gynaecological assessment happen in a single consultation with the same clinician. There is less fragmentation of care and, consequently, less stigma attached to any single element of it. Asking for an STI test is no different from asking for a smear — it is simply part of the appointment.

In the UK, sexual health services have historically been delivered separately from mainstream gynaecology, through dedicated GUM (genitourinary medicine) clinics. While these clinics provide an excellent service, the fact that sexual health exists as a separate system can inadvertently reinforce the idea that there is something unusual or shameful about seeking testing. Many of my patients tell me they would feel uncomfortable attending a sexual health clinic but are perfectly at ease discussing the same topics during a gynaecological consultation. I believe that integrating sexual health into routine women’s healthcare — as I do in my practice — is the most effective way to destigmatise screening and ensure that more women are tested.

Who should be screened?

STI screening is recommended if:

• You have a new sexual partner
• You or your partner have had unprotected sex with other partners
• You are experiencing symptoms such as unusual discharge, pelvic pain, pain during sex, or bleeding between periods
• You are planning a pregnancy (screening is part of good pre-conception care)
• You simply haven’t been tested recently and would like peace of mind

What I tell my patients is this: if you are sexually active and have ever had a new partner without testing beforehand, screening is sensible. Most STIs cause no symptoms at all, which is precisely why they spread so effectively. Chlamydia, for example, is asymptomatic in around 70% of women — you can carry it for months or even years without knowing.

Common presentations I see in clinic

While many STIs are asymptomatic, there are presentations that I encounter regularly and that should prompt testing. Unusual vaginal discharge is one of the most common reasons women attend my clinic. A thin, greyish discharge with a fishy odour is characteristic of bacterial vaginosis (which is not strictly an STI but is associated with sexual activity and can disrupt the vaginal microbiome). A thick, white, cottage-cheese-like discharge typically suggests thrush. However, a yellow-green or mucopurulent discharge, particularly if accompanied by pelvic discomfort, can indicate chlamydia or gonorrhoea and warrants immediate testing.

Intermenstrual bleeding or post-coital bleeding (bleeding after sex) is another presentation that prompts me to screen for STIs alongside performing a cervical examination. Chlamydial cervicitis is a common cause that is easily missed if testing is not offered. Dyspareunia (pain during sex) — particularly deep pelvic pain — can be a sign of pelvic inflammatory disease, which may result from untreated chlamydia or gonorrhoea ascending into the upper genital tract. Vulval ulceration, while less common, should always raise the possibility of herpes simplex virus or, more rarely, primary syphilis.

I also see women who present with recurrent thrush or BV that does not respond to standard treatment. In these cases, I always ensure a comprehensive STI screen has been performed, because co-infections can alter the vaginal environment and perpetuate symptoms.

What does each test involve? My testing protocol

Modern STI screening is straightforward, and most women are pleasantly surprised by how simple it is. In my practice, I offer a comprehensive sexual health screen that covers the infections most relevant to women’s health. Here is what each test looks like:

Chlamydia and gonorrhoea (vaginal swab — NAAT): These are tested using a nucleic acid amplification test, which is the gold standard. In most cases, this is a vaginal swab — which you can do yourself if you prefer — or a urine sample. The swab takes seconds and is not painful. NAAT testing is extremely accurate, with sensitivity above 95%. I routinely include both in every screen because gonorrhoea rates are rising and co-infection with chlamydia is common.

HIV and syphilis (blood test): These require a blood test. Modern fourth-generation HIV tests detect both the virus (p24 antigen) and antibodies, making them highly reliable from four weeks post-exposure. Syphilis serology picks up antibodies to the Treponema pallidum bacterium. A single blood draw covers both. Given the significant rise in syphilis cases in the UK, I include syphilis testing in every comprehensive screen regardless of perceived risk.

Hepatitis B and C (blood test): Also tested via blood. I routinely include these in a comprehensive screen, particularly for women who have travelled, had tattoos or piercings abroad, or have had multiple partners.

Mycoplasma genitalium (vaginal swab — NAAT): This is a relatively recently recognised pathogen that can cause cervicitis, pelvic inflammatory disease, and is increasingly associated with antibiotic resistance. I include it when clinically indicated, particularly in women with persistent discharge or pelvic pain that has not responded to initial treatment.

Herpes simplex virus (HSV): Routine blood testing for herpes is not recommended in asymptomatic individuals because serology cannot distinguish between oral and genital infection. However, if you have active lesions, I can perform a swab for HSV PCR testing, which is highly accurate.

HPV: Human papillomavirus is tested during cervical screening rather than as part of a standard STI panel. If you are due a smear test, we can combine this with your STI screen in a single appointment.

Understanding window periods

One of the most common questions I am asked is how soon after exposure a test will be accurate. Every infection has a “window period” — the time between exposure and the point at which the test can reliably detect it:

• Chlamydia and gonorrhoea: Two weeks after exposure
• HIV (4th generation test): Four weeks for a reliable result, though most guidelines recommend confirmatory testing at 12 weeks for complete certainty
• Syphilis: Four to six weeks, though it can occasionally take up to 12 weeks
• Hepatitis B: Six weeks
• Hepatitis C: Six to twelve weeks
• Mycoplasma genitalium: Two to five weeks

If you test too early, a negative result may not be definitive. I always discuss timing carefully with patients and, where appropriate, arrange a repeat test after the relevant window has passed. If you are concerned about a recent exposure, I recommend an initial screen at the earliest reliable time point for the most common infections, followed by a confirmatory blood test at 12 weeks to cover HIV, syphilis, and hepatitis with full confidence.

When you get your results

Results are typically available within two to five working days. If everything is negative, you will receive clear confirmation. If something does come back positive, there is no need to panic. I discuss the result with you in detail — what the infection is, what treatment involves, and what it means for your health going forward.

The vast majority of STIs are straightforward to treat. Chlamydia and gonorrhoea are treated with antibiotics, often a single dose. Syphilis requires a course of penicillin injections. HIV, while not curable, is managed exceptionally well with modern antiretroviral therapy — people living with HIV on treatment have a normal life expectancy and cannot transmit the virus when their viral load is undetectable.

Partner notification

If you test positive for an STI, your current and recent sexual partners need to be informed so they can be tested and treated too. I understand this can feel daunting. In my practice, I walk patients through their options: you can tell partners yourself, or a sexual health adviser can contact them anonymously on your behalf without revealing your identity. This process — called partner notification — is confidential and handled with sensitivity. It is a crucial step in breaking the chain of transmission.

How often should you be screened?

There is no single answer that fits everyone. As a general guide, I recommend screening with each new sexual partner, and at least annually if you are sexually active with more than one partner. Women under 25 are advised to screen for chlamydia yearly under the National Chlamydia Screening Programme. If you are in a long-term monogamous relationship and have both been tested, routine screening is less pressing — but a baseline test at the start of any new relationship is always wise. I also recommend a comprehensive screen as part of any well-woman check-up, particularly for women who have not been tested in more than a year.

STI screening in pregnancy

All pregnant women in the UK are offered screening for HIV, syphilis, and hepatitis B as part of routine antenatal care. This happens at the booking appointment, usually around 8–12 weeks. I often recommend a broader screen for chlamydia and gonorrhoea as well, particularly for younger women or those with new partners, because untreated infections can cause complications including preterm labour, low birth weight, and neonatal conjunctivitis. If you are planning a pregnancy, getting screened beforehand is the ideal approach. Untreated infections can also disrupt the vaginal microbiome, creating further health complications.

Reducing stigma around testing

I want to be direct about this: there is no moral dimension to an STI diagnosis. These are infections — caused by bacteria, viruses, or parasites — and they affect people of all backgrounds and relationship patterns. I often see women who feel ashamed simply for requesting a test. That reaction tells me how much work we still have to do in normalising sexual health care.

Getting tested is not a sign that something is wrong with your choices. It is a sign that you are taking responsibility for your health. I treat STI screening exactly the same way I treat a cervical smear or a blood pressure check — as routine, sensible healthcare. In my view, every sexually active woman should have access to confidential, non-judgmental screening as a standard part of her gynaecological care. The more we treat sexual health as ordinary healthcare, the more women will feel empowered to be tested — and the fewer infections will go undiagnosed.

Why private screening?

While sexual health clinics provide an excellent free service, many women prefer the privacy, comfort, and convenience of being tested during a gynaecological consultation. There is no waiting list, the environment is calm and unhurried, and results can be discussed in the context of your broader gynaecological health. In my clinic, STI screening fits naturally into a well-woman check or pre-conception assessment — it does not need to be a separate, anxiety-provoking appointment. It is also an ideal opportunity to review your contraception and discuss any other concerns.