What To Do After Unprotected Sex

Stay Calm

First, take a breath. Having unprotected sex — whether it was unplanned, a condom broke, or you missed contraception — is common, and there are steps you can take. Acting quickly improves your options.

Within 24 Hours

Emergency Contraception

The sooner you take emergency contraception, the more effective it is.

• Levonorgestrel pills (e.g., Plan B) — Available over the counter in many places. Most effective within the first 24 hours but can be taken up to 72 hours (3 days) after unprotected sex (WHO, NHS).
• Ulipristal acetate (e.g., ella) — Effective up to 120 hours (5 days). May require a prescription depending on your location.

Consider HIV Risk

If there is a risk of HIV exposure, PEP (post-exposure prophylaxis) should ideally be started within 72 hours. PEP is a course of antiretroviral medication taken for 28 days (CDC — Preventing HIV with PEP). It is available from hospitals, sexual health clinics, and some pharmacies. The sooner it is started, the more effective it is.

Within 5 Days

Copper IUD

A copper IUD can be inserted as emergency contraception up to 5 days after unprotected sex. It is the most effective form of emergency contraception (over 99%) and also provides ongoing contraception.

STI Considerations

Some STIs can be tested for soon after exposure, but most have a "window period" — the time between exposure and when a test can accurately detect an infection. During this time, avoid unprotected sex with others.

After 2 Weeks

Pregnancy Testing

Most home pregnancy tests become reliable approximately 2–3 weeks after unprotected sex, or from the first day of a missed period (NHS — Doing a pregnancy test). If you test too early, you may get a false negative. If your result is negative but your period does not arrive, repeat the test after a few days.

Some STI Tests

Certain STI tests (e.g., chlamydia, gonorrhoea) may be accurate from about 2 weeks after exposure, but testing windows vary by infection.

After 3 Months

HIV Testing

Most modern HIV tests are accurate by 4–6 weeks after exposure, but a test at 3 months after exposure provides a more definitive result (CDC). If you had PEP, testing timelines may differ — follow your clinician's guidance.

Syphilis and Other STIs

Some infections, such as syphilis, may take longer to appear on tests. A follow-up screen at 3 months is a good idea if you had a risk exposure.

HIV Prevention

• PEP — Should be started within 72 hours of a potential HIV exposure. It is a 28-day course of medication (CDC). Available from hospitals and sexual health clinics.
• PrEP — Pre-exposure prophylaxis is a preventive medication taken by people who are at ongoing risk of HIV. It is not an emergency measure but can be discussed with a healthcare provider as part of your ongoing HIV prevention plan.
• Condoms — The most accessible method of reducing HIV transmission risk during sex.

If You Were Assaulted

If you have been sexually assaulted, this is not your fault. You deserve support.

• Seek medical care as soon as possible — hospitals can provide emergency contraception, PEP, STI prophylaxis, forensic examination, and emotional support.
• You do not have to report to police to receive medical care, but you can if you choose to.
• In Kenya, you can contact Gender-Based Violence hotline: 1195 or go to any hospital.
• Globally, many countries have sexual assault crisis centres — search for services in your area.

When to Seek Urgent Help

Seek immediate medical attention if:

• You are experiencing severe abdominal pain
• You have heavy or unusual bleeding
• You have been assaulted
• You have symptoms of a serious allergic reaction
• You are having thoughts of self-harm
• You believe you have been exposed to HIV and need PEP urgently