What is it?

Hormonal methods of contraception intended for use by women who have had unprotected sex. There are two forms: the emergency pill and the IUD device.

How is the emergency contraceptive pill taken?

The emergency pill must be taken within 72 hours (three days) of sex. The sooner you take it, the more effective it is. Most types contain levels of synthetic oestrogen with progestogen - hormones that are similar to those found in the body - and work by preventing the egg from being implanted in the womb.

The emergency pill shouldn't be regarded as a contraceptive choice like the condom, diaphragm or the pill. This is because it can only be used occasionally to be 100% effective. Instead, consider it as a fail-safe should something go wrong with your chosen form of birth control. 

(Note that if you're unable to use an oestrogen-based hormonal contraceptive, ask your doctor to prescribe a progestogen-based emergency pill.)

One recently publicised pill, Ellaone, can be used up to five days after unprotected. It is 66% effective if taken within the usual morning after pill window of 72 hours, and 50 per cent effective after 120 hours (five days). As it is only available on prescription, Ellaone is unlikely to become the main method of emergency contraception at the moment.  

How does the IUD work?

The IUD (or 'coil') is a small, copper device that must be fitted inside the uterus by a doctor within five days of unprotected sex. It works in the same way as the emergency contraceptive pill, but can be fitted up to 120 hours (5 days) after unprotected sex.

It must be worn until your next period (when you're sure you aren't pregnant). It can also work as a regular contraceptive (but will only protect against pregnancy and not sex infections). Always discuss this with your doctor first.

Does emergency contraception cause an abortion?

No. Both methods work by preventing the egg from implanting in the womb - whether or not it has been fertilised.

Other essentials

• You might hear people refer to the emergency contraceptive pill as 'the morning after pill', which is misleading. The fact is it can be taken up to three days after unprotected sex, but no later.
• Some women who take the emergency pill may experience short-term side effects such as dizziness or nausea. If vomitting occurs within two hours of taking a pill, see your doctor. This is because the pill is absorbed into the body via the digestive system and throwing up could mess with its effectiveness as a contraceptive.

Drawbacks

• Neither the emergency contraceptive pill or the IUD protect against sex infection - if you've had unprotected sex you may want to have an STI test.
• Drawbacks to the IUD include a risk of heavy periods, spotting and possible pelvic infection.

Availability

Both the emergency pill and the IUD are available freely from a doctor at your local surgery, sexual health clinic, GUM centre or Brook Centre. If you're over 16, the emergency pill is also available over the counter from selected chemists. It costs around £25. In every case, it's vital that you seek help fast to keep your options open.

Updated: 07/06/2011