Lesbian & Bisexual Women: STI Risks and Screening

Lesbian and bisexual women can and do get sexually transmitted infections, so the "women who sleep with women don't need screening" idea is a myth. STIs pass through skin contact, shared fluids, and shared sex toys, and many infections cause no symptoms. The same risk-based screening rules apply: test on a schedule set by your partners and history, regardless of how you feel.

Why "no risk" is wrong for women who have sex with women

The myth comes from old assumptions that STIs only travel through penis-in-vagina sex. They don't. Chlamydia and gonorrhea live in mucous membranes and can move between partners through oral, digital (fingers), and genital-to-genital contact, as well as on shared toys that aren't cleaned or covered between uses. HPV and herpes spread by skin-to-skin contact, which condoms only partly cover. Bacterial vaginosis is unusually common between female partners. And bisexual women who also have male partners face the full range of routes. "Lower on average" is not "none," and averages don't protect any individual person.

Screening means testing when you feel completely fine. Silent infections, the ones with no discharge, no pain, and no sores, are exactly what routine screening is built to catch. How often you test is driven by your risk profile, not by symptoms you can notice.

How the test works

There's no single "STI test." Each infection has its own method, and the sample depends on where you've had contact:

• Chlamydia and gonorrhea are found with a NAAT (nucleic acid amplification test), which detects the bacteria's genetic material. The sample can be a urine specimen, a self-collected or clinician-collected vaginal swab, or a swab of the throat or rectum if you've had oral or anal contact at those sites. Vaginal swabs are generally the most sensitive sample for women.
• HIV and syphilis are blood tests — a finger-stick or a draw from your arm. HIV tests look for antibodies and/or the p24 antigen; syphilis uses a blood antibody screen confirmed by a second test.
• Herpes and HPV aren't part of routine asymptomatic screening. Herpes is usually tested by swabbing an active sore; HPV is checked through cervical (Pap) screening, which everyone with a cervix needs regardless of who they have sex with.

Throat and rectal infections are routinely missed because a urine test can't find them. The CDC specifically advises swabbing those sites for people who have oral or anal sex CDC screening guidance. If those sites apply to you, ask for them by name, since clinics don't always offer them automatically. You can start by booking an appointment to get tested.

When to test after exposure: the window

Every test has a window period — the gap between exposure and when the test can reliably detect an infection. Test too early and a real infection can read as negative. Chlamydia and gonorrhea NAATs turn positive within days to a couple of weeks. HIV and syphilis blood tests take longer because they often rely on your body producing detectable antibodies. If you have a specific exposure date, time your test to the window for that infection rather than rushing in the next morning. Our guide to when to test after exposure breaks down the timing for each infection.

If you had a recent high-risk exposure and want protection while you wait, that's a same-day clinician conversation rather than something to handle by testing alone.

Where to get tested and what it costs

You have several routes, and the right one depends on privacy, speed, and cost:

• Primary care or a gynecologist can fold STI screening into an annual visit — convenient if you already have a provider you're out to.
• Planned Parenthood and public health / STD clinics offer screening on a sliding scale, often free or low-cost, and they're used to seeing LGBTQ+ patients.
• Online and at-home test kits let you self-collect a sample (urine, vaginal, or multi-site swabs) and mail it to a lab — useful if asking a provider feels uncomfortable.

Costs vary widely by route and insurance, so it pays to check before you book. You can compare testing providers to weigh price, turnaround, and which sample sites each one covers. A common mistake is choosing a urine-only kit when you actually need throat or rectal swabs, so read what's included.

Reading your results and how accurate they are

NAATs for chlamydia and gonorrhea are highly sensitive and specific, which is why they're the standard. HIV and syphilis screens are also very accurate, with one caveat: a positive screen for either is followed by a confirmatory test before any diagnosis is final, because screening tests are tuned to miss as few infections as possible and can occasionally flag a false positive. A negative result is only as reliable as your timing. If you tested inside the window, repeat it after the window closes. A non-reactive HIV test taken well after exposure is reassuring.

If a result is positive

Most bacterial STIs — chlamydia, gonorrhea, syphilis — are curable with antibiotics, and your recent partners should be notified and treated so you don't pass it back and forth. See our treatment guidance for what to expect, and if HIV is involved, note that starting care early protects both your health and your partners — earlier hiv treatment can help prevention.

What the major guidelines actually recommend

Screening is risk-based, and the rules don't change because both partners are women. The USPSTF recommends everyone aged 15 to 65 be tested for HIV at least once, with extra testing for those at increased risk at any age USPSTF, HIV. It also recommends screening all sexually active women under 25 for chlamydia and gonorrhea every year, and older women with new or multiple partners or other risk factors USPSTF, chlamydia & gonorrhea. Pregnancy adds its own panel — everyone who's pregnant is screened for HIV and syphilis (and hepatitis B) because treating these protects the baby USPSTF, syphilis in pregnancy; see the full pregnancy sti screening panel.

The single most useful habit is to make testing routine: tie it to a new partner, an annual checkup, or starting PrEP, and when you book, ask specifically for throat or rectal swabs if those sites apply to you.

When to see a clinician

Book a visit rather than relying on a kit if you have symptoms — unusual discharge, pelvic or lower-belly pain, sores, bleeding between periods, or pain with sex — if a partner tells you they tested positive, if you're pregnant, or if you want a same-day conversation about prevention after a recent exposure. Symptoms can mean an infection that's moved beyond the cervix, and that needs a clinician's eyes rather than a mail-in test.