Unprotected Sex: What to Do Next and When Emergency Contraception Can Help
Unprotected sex can leave you worried about pregnancy, sexually transmitted infections (STIs), or both. The most important thing is to know what options are still available and whether timing matters.
If you do not want to become pregnant, emergency contraception may help prevent pregnancy after unprotected sex. Some options can be used up to 5 days afterward, but acting sooner is generally better.
This guide explains what to do after unprotected sex, how emergency contraception works, when to take a pregnancy test, and when to consider STI testing.
What Counts as Unprotected Sex?
Unprotected sex does not only mean having sex without a condom. Pregnancy risk may also occur when contraception was used incorrectly or failed.
Examples include:
- Penis-in-vagina sex without a condom or another reliable contraceptive method
- A condom breaking, slipping, or coming off
- Missing birth control pills or using them incorrectly
- Being late for a contraceptive injection or other scheduled contraceptive method
- Using withdrawal as the only method of contraception
- Incorrect use or failure of another contraceptive method
The actual chance of pregnancy depends on several factors, including whether ovulation occurred around the time of sex and whether any contraception was used.
What Should You Do After Unprotected Sex?
If pregnancy is not desired, first determine approximately how much time has passed since the unprotected sex.
This matters because emergency contraception has a limited window in which it can be used.
If It Has Been Less Than 72 Hours
Levonorgestrel emergency contraceptive pills are commonly used within 72 hours (3 days) after unprotected sex.
They should generally be taken as soon as possible because effectiveness can decrease as more time passes.
If It Has Been 72 to 120 Hours
Some emergency contraception options can still be used up to 120 hours (5 days) after unprotected sex.
Ulipristal acetate is an emergency contraceptive pill designed for use within this 5-day window. A copper intrauterine device (IUD), when appropriate and available through a qualified healthcare provider, can also be a highly effective form of emergency contraception.
Availability of particular emergency contraception options varies by country, so consider asking a pharmacist, doctor, or reproductive-health provider what is available to you.
How Do Emergency Contraceptive Pills Work?
Emergency contraceptive pills primarily work by preventing or delaying ovulation, meaning the release of an egg from the ovary.
If no egg is available for fertilization, pregnancy cannot begin from that episode of sex.
Emergency contraception is not the same as medication used to end an established pregnancy. Emergency contraceptive pills do not terminate an existing pregnancy.
What Types of Emergency Contraception Are Available?
Levonorgestrel Emergency Contraception
Levonorgestrel is a hormone used in many emergency contraceptive pills. It is generally recommended as soon as possible after unprotected sex and is commonly used within 72 hours.
The sooner it is taken, the better the chance of preventing pregnancy.
Ulipristal Acetate
Ulipristal acetate is another type of emergency contraceptive pill. It can be used within 120 hours, or 5 days, after unprotected sex.
Because interactions with hormonal contraception need to be considered after taking ulipristal, follow the product instructions or advice from a healthcare professional.
Copper IUD
A copper IUD can also be used as emergency contraception when inserted by a trained healthcare professional within the appropriate time window.
It also provides ongoing contraception after insertion.
Does Emergency Contraception Guarantee You Won't Get Pregnant?
No method of emergency contraception guarantees that pregnancy will be prevented.
Effectiveness depends on factors such as the type of emergency contraception used, how quickly it was used, and where you were in your menstrual cycle.
This is why taking a pregnancy test later may still be necessary even after using emergency contraception.
What If He Didn't Finish Inside?
Pregnancy is less likely when ejaculation does not occur inside the vagina, but the risk is not zero.
Withdrawal can fail if semen enters the vagina or if withdrawal happens too late. Because it can be difficult to know exactly what happened during sex, withdrawal is less reliable than many established contraceptive methods.
If pregnancy would be a serious concern and the sex occurred within the emergency contraception window, you can discuss emergency contraception with a healthcare professional or pharmacist.
What If the Condom Broke?
If a condom broke or slipped during vaginal sex, pregnancy may be possible if semen entered the vagina.
Emergency contraception may be considered if you are not otherwise protected by an effective contraceptive method.
A broken condom can also mean possible exposure to an STI, so STI testing or medical advice may be appropriate depending on the circumstances.
Can You Know Whether You Were Ovulating?
It is difficult to determine the exact day of ovulation based only on a calendar.
Ovulation can occur earlier or later than expected, particularly when cycles are irregular. Stress, illness, travel, sleep changes, and other factors may also affect cycle timing.
Period-tracking apps can help identify patterns, but they should not be treated as a guarantee that a particular day is pregnancy-free.
When Should You Take a Pregnancy Test?
If your next period does not arrive when expected, you can take a home pregnancy test.
Pregnancy tests are generally most reliable from the first day of a missed period when used correctly.
If you have irregular periods or do not know when your next period is due, consider testing at least 21 days after the episode of unprotected sex.
If the result is negative but your period still does not arrive, repeat the test after a few days or speak with a healthcare professional.
Can Emergency Contraception Change Your Next Period?
Yes. Your next period may arrive somewhat earlier or later than expected after taking an emergency contraceptive pill.
You may also notice temporary changes in bleeding or spotting.
A change in your next period does not automatically mean you're pregnant. However, if your period is significantly delayed, taking a pregnancy test is appropriate.
What About Sexually Transmitted Infections?
Emergency contraception prevents pregnancy; it does not protect against sexually transmitted infections.
If you had sex without a condom with a partner whose STI status is unknown, consider speaking with a healthcare provider or sexual-health clinic about testing.
Different infections have different testing windows, so testing immediately after exposure may not detect every infection.
HIV Exposure
If you believe you may have been exposed to HIV, seek medical care promptly.
HIV post-exposure prophylaxis (PEP) is medication that can reduce the chance of acquiring HIV after a possible exposure. It must be started within 72 hours, and the sooner it is started, the better.
When Should You Seek Medical Care?
Consider speaking with a healthcare professional if you are unsure which emergency contraception option is appropriate, have questions about your regular contraception, or are concerned about possible STI exposure.
Seek urgent medical attention if you later have a positive pregnancy test or possible pregnancy along with symptoms such as:
- Severe or worsening abdominal or pelvic pain
- Heavy vaginal bleeding
- Severe dizziness or fainting
- Shoulder-tip pain together with abdominal pain
These symptoms require medical assessment because an ectopic pregnancy is one possible cause.
Frequently Asked Questions
Can I get pregnant from one time of unprotected sex?
Yes. Pregnancy can occur after a single episode of unprotected vaginal sex if sperm are present and fertilization occurs.
Can I take emergency contraception the next morning?
Yes. Emergency contraception does not have to be taken literally the “morning after.” If an appropriate emergency contraceptive pill is available, it should generally be taken as soon as possible within its recommended time window.
Is it too late after 3 days?
Not necessarily. Some emergency contraception options can be used for up to 120 hours (5 days) after unprotected sex. Ask a healthcare professional or pharmacist about the options available to you.
Does emergency contraception cause abortion?
No. Emergency contraceptive pills work primarily by preventing or delaying ovulation and do not terminate an established pregnancy.
Can I have unprotected sex again after taking an emergency contraceptive pill?
Taking an emergency contraceptive pill does not necessarily protect you from pregnancy if you have unprotected sex again later in the same menstrual cycle. Use condoms or another appropriate contraceptive method for ongoing protection.
The Bottom Line
If you've had unprotected sex and do not want to become pregnant, timing matters.
Levonorgestrel emergency contraceptive pills are commonly used within 72 hours, while some emergency contraception options can be used for up to 120 hours after sex. Emergency contraception should generally be used as soon as possible when appropriate.
Remember that emergency contraception does not protect against STIs. If there was a possible STI or HIV exposure, seek appropriate testing or medical advice as soon as possible.
If your next period is late, take a pregnancy test at the appropriate time rather than relying on symptoms alone.
Sources
- World Health Organization (WHO) — Emergency contraception
- U.S. Centers for Disease Control and Prevention (CDC) — Emergency contraception and contraceptive guidance
- U.S. Centers for Disease Control and Prevention (CDC) — HIV post-exposure prophylaxis (PEP)
- American College of Obstetricians and Gynecologists (ACOG) — Emergency contraception
- NHS — Emergency contraception
- NHS — Doing a pregnancy test
Priva Health Editorial Team
This article provides general health information and does not replace advice, diagnosis, or treatment from a qualified healthcare professional.