Emergency Contraception

What is the Morning After Pill?

The morning after pill is a term often used to describe an emergency contraceptive pill. These tablets can be taken shortly after an episode of unprotected sex to prevent pregnancy. 

There are two main emergency contraceptive pills available in the UK. 

Levonelle - effective for up to 72 hours or 3 days after unprotected sex. Contains the active ingredient levonorgestrel, which is a synthetic version of the human sex hormone progesterone.
EllaOne - effective for up to 120 hours after unprotected sex (5 days). Contains the active ingredient ulipristal acetate. This interferes with how progesterone works.
 Neither pill is 100% effective, but both are more effective the sooner they are taken. 

The morning after pill is a common term for a tablet used as a form of emergency contraception. Where regular contraception has failed, emergency contraception can be used to prevent an unwanted pregnancy. 

How Effective is it?

It’s important to take the morning after pill as soon as possible after an incident of unprotected sex in order to maximise its effectiveness. 

Levonelle is most effective when taken within 12 hours of unprotected sex, although it can be effective for up to 72 hours after sex. You should bear in mind, however, that this effectiveness decreases over time.

 Levonelle is thought to prevent:

up to 95% of pregnancies if taken within 24 hours
up to 85% if taken within 48 hours
up to 58% if taken within 72 hours
Overall, EllaOne has been shown to be 98-99% effective in preventing pregnancy. This means that 1 or 2 in every 100 women will still become pregnant after using the pill. For this reason, it’s still important to consider you may be pregnant until you have been able to confirm the pill has worked. 

How it works

The morning after pill works by stopping or delaying ovulation. This means your egg is not released, or its release is delayed. If your egg’s release is stopped, sperm is unable to reach the egg to fertilise it, and so pregnancy is prevented.

If ovulation occurs before you take the pill, there is a risk sperm can fertilise the egg, and you will become pregnant. 

In addition to this mechanism, there are some additional effects that work to prevent pregnancy in case an egg is released. It makes it harder for sperm to reach the egg and also for the egg to implant to the wall of the uterus.

These methods of action mean that emergency contraception is highly successful in stopping pregnancy.

When can I take it?

If you are at risk of unwanted pregnancy, the morning after pill should be taken as soon as possible after unprotected sex. Levonelle however, is not effective past 72 hours after sex, while EllaOne is not effective past 120 hours after sex. If you have missed these cut-offs, you should see your doctor or nurse for alternative options.

Levonelle is effective up to 72 hours (3 days) after sex but it is not effective if taken after this time. EllaOne is effective for longer - it can be taken up to 120 hours (5 days) after sex.

Sick after taking the morning after pill?

If you vomit within 3 hours of taking your dose, another dose is likely required to make sure it works properly. This is because the medication may not have been sufficiently absorbed into your body. You should speak to your doctor or pharmacist if this has happened to you. 

What other options are there?

If you are too late to take Levonelle, you can see your GP to discuss fitting a contraceptive coil. This is also called the intrauterine device (IUD), another type of emergency contraception. This can be inserted up to 120 hours (5 days) after unprotected sex or contraceptive failure.  

An IUD will act to prevent fertilisation and is the most effective of the emergency contraceptive methods. It is, however, more intrusive and you will need to go to a clinic to have an IUD fitted. 

You can also read more information on safe sex here. Using regular methods of contraception may also be advisable if you are sexually active and not already on the pill. 

STIs and The Morning After Pill

The morning after pill will not prevent you from contracting sexually transmitted infections (STIs). If you require the morning after pill after sex without a condom and are worried you may have an STI, you can drop into a sexual health clinic near you.

Morning After Pill Side Effects

The most common side effects of the medication include tiredness, headaches and sickness. You may also experience abdominal pains, dizziness or breast tenderness. 

You may also experience some light bleeds, or 'spotting' after taking the pill. It might affect your menstrual cycle and cause your next period to be earlier or later. If your next period is more than 5 days late, you should take a pregnancy test to check if you are pregnant.

For a full list of side effects, you can read the patient information leaflets or 'Side effects of the morning after pill'. Find the information leaflets online for EllaOne and Levonelle.