What is emergency contraception?

Emergency contraception is a method of birth control used to prevent pregnancy from occurring after engaging in unprotected sexual intercourse. Unlike other methods of birth control, you can take emergency contraception after you have had sex.

It is different from medicines used to end a pregnancy. If you are already pregnant, they will have no contraceptive effect. Hence, emergency contraception does not induce abortions.

As the name suggests, emergency contraception is for emergencies and should not be used as a substitute for regular birth control, which has fewer side effects and costs less.

How does it work?

Emergency contraception works mainly by blocking or delaying egg release from the ovary (ovulation), stopping fertilization, preventing a fertilized egg from attaching to the womb, or blocking the effects of key hormones necessary for pregnancy. The net effect of all these processes is to prevent pregnancy from occurring.

Emergency contraception does not prevent sexually transmitted diseases (STDs). The best way to avoid getting STDs is to maintain a monogamous relationship. If that is not possible, use a latex condom correctly every time you have sex.

intrauterine device
3d rendered illustration of an intra-uterine device.

When to use Emergency Contraception

You can use emergency contraception in a number of situations following sexual intercourse. These include:

  • When no contraceptive has been used.
  • Cases of sexual assault when the woman was not protected by an effective contraceptive method.
  • There is concern about possible contraceptive failure, from improper or incorrect use, such as condom breakage, slippage, or incorrect use; dislodgment, breakage, tearing, or early removal of a diaphragm or cervical cap; failed withdrawal, and more.

What are the available options for Emergency Contraception?

There are two types of emergency contraception

  1. Emergency contraception pills (ECP)
  2. Intra-uterine device

Emergency Contraception Pills (ECP)

morning after oill
The Morning After Pill calendar note

ECPs are also called morning after pill. Emergency contraception pills should be taken as soon as possible within 5 days of unprotected sexual intercourse. The various forms are:

  1. Hormone-based emergency contraception pills. It contains a hormone called levonorgestrel and can come as a single dose (1.5 mg) or as a split dose (1 dose of 0.75 mg of levonorgestrel followed by a second dose of 0.75 mg of levonorgestrel 12 hours later). It is most effective when you take it within 3 days of unprotected sexual intercourse. Common brand names are Postinor-1, Postinor-2, Postrelle -1, Postella-1, NorLevo, NorLevo-1, Levonelle-1 and Levonelle-2.
  2. Ulipristal acetate (UPA). It is a non-hormonal medicine that blocks the effects of key hormones necessary for pregnancy to occur. Ulipristal acetate and hormone-based ECPs have similar effectiveness when taken within 3 days after unprotected sexual intercourse. However, UPA is more effective than the hormone-based ECPs 3–5 days after unprotected sexual intercourse. An example is EllaOne.
  3. Combined estrogen and progestin pill. It is less effective than UPA or hormone-based ECPs and is associated with more frequent side effects.
Emergency contraceptive pills on pharmacy counter with colorful pills strips background.

What are the side effects of ECPs?

There are no serious or long-term side effects from taking the emergency contraceptive pill. But it can cause:

  1. Nausea
  2. Vomiting
  3. Breast tenderness
  4. abdominal pain
  5. headache
  6. changes to your next period – it can come early, late, or more painful than usual
  7. feeling or being sick

See a doctor if these symptoms persist for days or you suspect pregnancy.

Who can use the emergency pill?

Most women can use the ECP. This includes those who cannot use hormonal contraception, such as the contraceptive patch and combined pill. Girls below 16 years old can also use it.

But you may not be able to take the emergency contraceptive pill if you react to any of its constituents, have severe asthma or take any drugs that may interact with it, such as:

  • some less commonly used antibiotics such as rifampicin and rifabutin.
  • some medicines used to treat HIV, tuberculosis, and epilepsy.
  • medicine to make your stomach less acidic, such as omeprazole
  • St John’s Wort, a herbal medication.

Intrauterine device

Holding an IUD birth control copper coil device in hand, used for contraception

The intrauterine device (IUD) is a small, T-shaped plastic and copper device that is put into your womb by a doctor. It releases copper to stop the egg from attaching to your womb or being fertilized.

It can be inserted up to 5 days after unprotected sex, or up to 5 days after the earliest time you could have released an egg (ovulated), to prevent pregnancy. You can also choose to have the IUD left in as an ongoing method of contraception.

How effective is the IUD as an emergency contraception?

The emergency IUD is the most effective method of emergency contraception, fewer than 1% of women who use the intrauterine device get pregnant.

It’s more effective than the ECPs at preventing pregnancy after unprotected sex.

Side effects of the IUD

Side effects after having an intrauterine device fitted are uncommon, but can include:

  1. infection
  2. pain
  3. damage to the womb
  4. the IUD can be displaced from the womb
  5. changes to your menstrual period if you continue to use it as a regular method of contraception

What kind of Emergency Contraception is best for me?

The best emergency contraception for you depends on the following factors:

  1. When you had unprotected sex– You have up to 5 days after unprotected sex to use emergency contraception.
  • Hormone-based ECP works better the sooner you take it. It is not that effective after 3 days.
  • It is advisable to take Ulipristal acetate as soon as you can. But it is more effective than hormone-based ECP, no matter when you take it.
  • The intrauterine device is the best at preventing pregnancy, and it is as effective on day 5 as on day 1.

2. How much you weigh

  • Hormone-based ECP may not work if your weight is above 70kg.
  • Ulipristal acetate may be less effective if you weigh above 88kg.
  • The IUD works just as well no matter your weight.

3. Which type is easiest for you to get

  • Hormone-based ECP is usually the easiest — anyone can get it over-the-counter without a prescription at most pharmacies, no matter your age or gender.
  • Ulipristal acetate can difficult to get because you need a prescription. 
  • The intrauterine device can be hard to get within five days because you need an appointment for a nurse or doctor to insert it.

4. Whether you’re breastfeeding

  • Hormone-based ECP and the copper IUD do not affect your breast milk.
  • If you use Ulipristal acetate, you will need to pump and discard your breast milk for 36 hours after taking it.

Does Emergency Contraception Affect Fertility in the Future?

No. Taking emergency contraception does not affect your ability to have a baby later. If you got an IUD for emergency contraception, a doctor will need to remove it before you can get pregnant.


Emergency Contraceptive is one of the most effective methods of preventing pregnancy after sexual intercourse with little or no side effects. But can sometimes be cumbersome when unprotected sex becomes regular.

If you are not using a regular method of contraception, you can consider doing so to protect yourself from unwanted pregnancy.

There are several methods of contraception that give long-term protection, so you do not have to think about them once they are in place, or remember to use or take them every day or every time you have sex.

These methods include the:

Was this article helpful?


F.O. Adagbonyin, MB.BS in view, certified content creator at Medblog180 and MedicWord, licensed google writer, and contributing writer at Wikimedia Foundation.

Leave a Reply

Your email address will not be published.