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Emergency contraception is a way to prevent pregnancy if:
Using emergency contraception right away can prevent an unwanted pregnancy. And it can keep you from worrying while you wait for your next period to start.
There are two main types of emergency contraception: pills and the copper intrauterine device (IUD). Pills work well, don't cost a lot, and are usually easy to get. The copper IUD works very well, but it has to be inserted by a healthcare provider.
Emergency contraception pills work by preventing ovulation, fertilization, or implantation.
The hormones in these pills may prevent fertilization by stopping the ovary from releasing an egg (ovum). They also make the fallopian tubes less likely to move an egg toward the uterus. The pills are also thought to thin the lining of the uterus, or endometrium. The thickened endometrium is where a fertilized egg would normally implant and grow.
A copper IUD for emergency contraception may prevent fertilization or implantation.
Where you get emergency contraception may depend on which type you use.
You can get emergency contraception without a prescription at most drugstores.
Some types of emergency contraception, such as ulipristal acetate (for example, ella) are available only from family planning clinics or with a prescription from a healthcare provider.
If you already have birth control pills on hand, you may be able to use them for emergency birth control. Talk to your healthcare provider to find out the correct doses.
You can get an IUD from many healthcare providers, from university and public health clinics, and in most hospital emergency rooms. An IUD has to be inserted by a healthcare provider.
Some pharmacists won't sell emergency contraception or fill prescriptions for birth control pills. If this happens to you, ask for the location of a pharmacist who will. You can also call Action Canada for Sexual Health and Rights at 1-888-642-2725 or visit the website at https://www.actioncanadashr.org/resources/services to find services near you.
How you use emergency contraception depends on which type you use.
The pills come in 1-pill or 2-pill packages. Follow the directions in the package, or take them as your healthcare provider directs you to.
You can take emergency contraception up to 5 days after unprotected sex.
Talk to your healthcare provider to find out the correct doses. Take the dose as soon as you can. Then you take a second dose 12 hours later. The dose depends on the type of pill.
If you use birth control pills for emergency contraception, keep these things in mind:
A healthcare provider inserts an IUD up to 5 days after unprotected sex.
The sooner you use emergency contraception, the more likely it is to prevent pregnancy. Overall:
If you are overweight, emergency contraception pills may not work as well to prevent a pregnancy. Talk with your healthcare provider about methods that aren't affected by your weight, such as an IUD.
Your healthcare provider may suggest that you have a pregnancy test about 3 weeks after using emergency contraception.
Unless you get an IUD, emergency contraception doesn't take the place of regular birth control. Find a good method of birth control you can use every time you have sex.
Emergency contraception pills won't protect you for the rest of your cycle. Use condoms or another barrier method of birth control until you start your period. If you usually use a hormonal method of birth control, such as birth control pills, the vaginal ring, or the patch, check with your healthcare provider about when to start using them again.
But accidents can happen. It is a good idea to keep a set of emergency contraception pills on hand in case you ever need it.
Emergency contraception may cause some side effects.
Call your healthcare provider if you have a headache, dizziness, or belly pain that is severe or that lasts longer than 1 week.
If you are already pregnant, most pills won't harm the fetus. But some pills, such as ulipristal, may cause problems with the pregnancy. More research is needed to know for sure. An IUD could cause problems with the pregnancy.
CitationsBlack A, et al. (2015). Canadian contraception consensus (part 1 of 4). Journal of Obstetrics and Gynaecology Canada, 37(10): S1–S28. http://sogc.org/wp-content/uploads/2015/11/gui329Pt1CPG1510E.pdf. Accessed February 9, 2016.Ti AJ, et al. (2020). Effectiveness and safety of extending intrauterine device duration: A systematic review. American Journal of Obstetrics and Gynecology, 223(1): 24–35.e3. DOI: 10.1016/j.ajog.2020.01.014. Accessed August 29, 2022.
Adaptation Date: 2/21/2023
Adapted By: Alberta Health Services
Adaptation Reviewed By: Alberta Health Services
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