STI Screening: What to Expect (Women's Guide)

In my clinic, the first thing most women say when they sit down for a screen is that they're dreading the internal exam. Here's the reassuring bit: for a routine screen with no symptoms, there usually isn't one. An STI screen is quick and, for women with no symptoms, usually needs no internal examination. A standard screen checks for chlamydia, gonorrhoea, HIV and syphilis using a urine sample, a self-taken vaginal swab and a blood test. Results typically take a few days to two weeks. If you'd rather be seen discreetly and fast, private STI screening in London can usually be arranged same-day.

What actually happens at an STI screen

For a routine screen with no symptoms, you'll usually give a urine sample, take your own vaginal swab, and have a blood test — no speculum, no stirrups. The whole visit takes minutes, not the ordeal most women brace themselves for.

Here's the order it tends to run in:

1. You register, and it's confidential. Your results don't go to your employer, your partner, or your GP unless you ask them to. This is the thing I reassure people about most. 2. Someone asks about your sexual history. When you last had sex, whether partners were male or female, what kind of sex, any symptoms. These aren't nosy questions — they decide which samples to take and which sites to swab. 3. You give a urine sample. For chlamydia and gonorrhoea, first-catch urine works well in women. 4. You take your own vaginal swab. A self-taken swab is a small cotton bud you insert yourself, in private. It's as accurate as one a clinician takes, and most women find it far less awkward than they feared. 5. You have a blood test. A small sample from your arm checks for HIV and syphilis.

An internal examination — a speculum, the kind you'd have for a smear — is only needed if you have symptoms like unusual discharge, pain or bleeding, or if a doctor needs to look for a specific cause. No symptoms, no speculum. That's the usual rule for a routine screen.

And if you do have symptoms? The examination is brief, explained as it goes, and you can ask to stop at any point. This is exactly the situation where being seen in person by a gynaecologist, rather than posting off a kit, earns its keep — a swab can name an infection, but it can't look, and some causes of discharge or pain aren't STIs at all. Either way, you're welcome to bring someone with you, or to ask for a chaperone.

When can you test? Window periods explained

Testing too soon can miss an infection. Chlamydia and gonorrhoea are reliable from about two weeks after sex, HIV up to 45 days, and syphilis up to 12 weeks. The gap between exposure and a reliable result is called the window period — the time your body needs before a test can pick up the infection, or the antibodies to it.

This matters more than most people realise. A woman comes in after a new-partner scare, tests on day three, gets a negative, and walks out relieved. But day three is far too early for most of these tests. That negative told her almost nothing. If you test inside the window, you'll usually be advised to test again once enough time has passed.

One time-critical exception: if you think you've been exposed to HIV in the last 72 hours, PEP — a short course of medication that can stop infection taking hold — may be an option. That's an emergency to act on now, not something to wait and test for.

What a standard screen does — and doesn't — cover

A standard screen covers chlamydia, gonorrhoea, HIV and syphilis; herpes and HPV aren't included unless you have symptoms or a specific reason. This surprises people. A screen doesn't test for everything, and no clinic can hand you a clean bill on infections it never looked for.

Herpes is usually only tested if you have a sore or blister to swab. HPV isn't part of an STI screen at all — it's checked through cervical (smear) screening, which has a different purpose entirely. If you're due one, our guide explains why cervical screening is a separate test from anything on this page.

Depending on your history, you might be offered more: trichomoniasis, Mycoplasma genitalium, or hepatitis B and C. Throat and rectal swabs are added according to the kind of sex you've had, not by default. If you want the wider picture, see our full guide to STI testing. And if a new relationship has you thinking about protection too, it's worth reading up on contraception options.

Do you need a screen if you have no symptoms?

Yes — most chlamydia and gonorrhoea in women causes no symptoms, so feeling well doesn't rule out infection. This is the single most important thing to understand about screening. You can carry, and pass on, an infection for months without a single sign.

So who should test, and when? Anyone with a new partner. Anyone who's had sex they're worried about. If you're under 25 and sexually active, an annual chlamydia test is advised, plus one on each change of partner. London has more reason than most: it has the highest STI rate of any English region, with over 122,000 new diagnoses in residents in 2024.

Screening when you feel fine isn't over-cautious. It's how these infections are actually caught — before they cause problems like pelvic inflammatory disease, which can affect fertility. A quick test now saves a lot later.

Getting screened in London: your options

In London you can screen free at an NHS sexual health clinic, order a free online postal kit, or book a private same-day appointment for speed and privacy. All three are valid — the right one depends on whether you have symptoms, how quickly you want answers, and how private you need it to feel.

My French patients often expect a walk-in-lab model. Since September 2024, France's "Mon test IST" lets you screen at any laboratory with no prescription and no appointment for HIV, chlamydia, gonorrhoea, syphilis and hepatitis B — free under 26, and largely reimbursed after. The UK works differently. There's no single walk-in labo, but between the NHS clinics, free postal kits and private appointments, you have the same reach — it's simply organised into separate routes. The maze my French patients describe — GP or clinic? clinic or kit? — usually comes down to one question: do you have symptoms? If yes, be seen in person. If not, any of the three works, and the postal kit is the least effort. If you'd like to be seen by a doctor who can also examine and reassure, book private STI screening in London.

How long do results take — and who sees them?

Results typically take a few days to two weeks, and they go to you — not your GP, your employer or your partner. Exactly where in that range you land depends on the test and the service. Most services text you when everything is negative and phone if something needs treating — so an unexpected call isn't a reason to panic on its own. But do answer it.

Two things I tell every patient. First: no news is not a result. Samples occasionally fail and need repeating, so if two weeks pass in silence, chase it. Second: confidentiality here is real, not a courtesy phrase. Sexual health services in the UK keep their records separate from your general medical notes, and nothing is passed to your GP unless you agree to it. Postal kits arrive in plain packaging, with nothing on the envelope to say what's inside, and go back the same way. My French patients often ask whether a positive result follows them somehow — into an employment record, back to a partner, over to their GP. It doesn't, unless you choose to share it.

What happens if a result is positive

Most STIs are easily treated — often with a single course of antibiotics — and the clinic helps with confidential partner notification. A positive result is not a catastrophe, and it's not a judgement. It's a treatable diagnosis, and you'll be looked after through it.

Partner notification means recent partners are told they should test, and it can be done anonymously on your behalf if you prefer. After treatment for chlamydia or gonorrhoea, a retest at three months is usually advised, because re-infection from an untreated partner is common. If symptoms keep coming back, or you're getting recurrent UTIs and aren't sure what's behind them, that's worth seeing a gynaecologist about properly.

If you're not sure where to start, a broader well-woman check can fold sexual health into a wider look at how you're doing. Whatever's prompted you to read this — a scare, a new relationship, or just wanting to stay on top of your health — screening is a small, quick thing that buys real peace of mind. If you'd like it handled discreetly, by a doctor who can examine and reassure as well as test, you can book a private appointment. This article is for information and isn't a substitute for individual medical advice.