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We get a lot of questions from teens who are wondering if they can prevent pregnancy after intercourse, whether the concern is due to a broken condom or from not using any method of contraception in the first place. Regardless of how it happened, there is something that can reduce the risk of pregnancy if used within 120 hours (or with an IUD, eight days) of your risk. That something is Emergency Contraception.
Additional Sources for Effectiveness Ratings and Use:
The What, the Why, the Where, the When, and the How-to: Emergency contraception (EC) is a method of birth control, in that it is a means to prevent pregnancy before it occurs. Plan B can prevent pregnancy primarily, by delaying or inhibiting ovulation and inhibiting fertilization, and that may be the only way it works, as it is the way it has been proven to work in clinical studies.
As explained by the ARHP, "although early studies indicated that alterations in the endometrium after treatment with the regimen might impair receptivity to implantation of a fertilized egg, more recent studies have found no such effects on the endometrium. Additional possible mechanisms include interference with corpus luteum function; thickening of the cervical mucus resulting in trapping of sperm; alterations in the tubal transport of sperm, egg, or embryo; and direct inhibition of fertilization. No clinical data exist regarding the last three possibilities."
Plenty of people -- no thanks to a lot of purposefully misleading propaganda -- confuse emergency contraception with medical abortion (sometimes called RU486 or M&M, an abbreviation for mifepristone and misoprostol, two medications used for medical abortion/ the abortion pill), but emergency contraception cannot be used to terminate an existing pregnancy: it can only help prevent one. If a pregnancy has already occurred, EC will not be effective: only a method of abortion can be used to purposefully terminate a pregnancy. Where some of the confusion comes in is that unlike other methods of contraception, EC can be used after intercourse, rather than before.
The most prevalent and simple method of emergency contraception is an oral medication, called Plan B or the Morning-After Pill. It is a progestin-only hormone -- levonorgestrel -- the same one used in the Mirena IUD and in some types of contraceptive implants and birth control pills. It is safe to use for women who cannot use or are sensitive to estrogen. Women who are allergic or sensitive to levonorgestrel should not use Plan B.
If you've heard about people refusing to fill EC prescriptions or objecting to EC but NOT objecting to other methods of hormonal birth control, you can perhaps now see the giant flaw in that idea. The only thing that makes EC different from other combination hormonal contraceptives is that it is taken after a risk, rather than before, though even that is only partially true, since ongoing hormonal birth control is taken both before AND after, as those methods administer hormones to the body daily.
One critical difference between EC and other contraceptives is that it is NOT meant to be used as an ongoing or sole contraceptive. Not only would that get mighty expensive for most people -- EC pills can cost as much as $50 and an IUD inserted as EC can cost as much as $400 -- it's also not as effective as other methods of contraception. It contains a substantially higher dose of hormones than other hormonal methods, and is not designed for, nor has been studied for, regular use. Too, because it is a big dose of hormones all at once, ongoing side effects for most women would be pretty unmanageable: Plan B often makes many women very nauseated -- plenty to the point of vomiting -- it often causes unpredictable bleeding and periods for a little while after use, and can result in some killer headaches for some women.
In many countries, emergency contraception pills can be obtained over-the-counter at pharmacies, or through sexual healthcare providers or general health clinics, without an exam. In the United States, currently those 17 and over can obtain EC pills without a prescription, though in some states, those of all ages can access EC via a pharmacy. Some under 17 will need to get EC through a healthcare provider, such as their general doctor or gynecologist, a sexual or general health clinic, or through a hospital (including the emergency room), or find someone they know over 17 to obtain it for them over-the-counter (which is perfectly acceptable). Emergency contraception pills usually cost between $30 and $60 per use, though are discounted at some clinics or public health service providers. Some clinics may request parental consent before prescribing ECPs to minors, but they are not required by law to do so.
Legal policy about refusals -- based on sexual discrimination, rules of professional conduct and medical ethics, but also rights of personal belief on the part of pharmacists -- has been established in some states, and is still in the process of being established in others. If you or a friend are refused any form of contraception, including emergency contraception, and you want to take action about a refusal in the United States, you can contact the Reproductive Rights wing of the ACLU or the National Women's Law Center.
If you have just had sex that may have resulted in a high pregnancy risk (if you're not sure what sort of sexual activity involves a pregnancy risk, check out our pregnancy risk assessment flowcharts) and you do not wish to become pregnant, you should obtain ECPs as soon as possible: the sooner they are used, the more likely they are to be effective.
Once you've found a healthcare provider or pharmacy who can prescribe/dispense ECP, you'll need to call their office or visit in person. Be prepared to answer questions like: • What was your last menstrual period?
• When did the sexual activity happen?
• Was it the only possible pregnancy risk during this menstrual cycle?
• You may also be asked if you've had a pelvic exam or pap smear during the past year, and you may also be asked for a medical history.
Once the healthcare practitioner has determined that you have a pregnancy risk, she or he will discuss with you how to obtain the ECPs and how to take them. They may phone a prescription to a local pharmacy, or they may give them to you in person. Follow the instructions carefully, and call the healthcare practitioner immediately if you have any questions.
Plan B is a package of either one or two pills. With packages of two, you take both together or, if you're prone to stomach upset from the pills, take one, then 12 hours later, take the other. If you throw up inside an hour of taking your pills, you may need to get a new pack and start over. It's always smart to take a pregnancy test two weeks or so after using EC, especially if you have not yet had your period at that time.
Some birth control pills can also be used as emergency contraception, such as Alesse, Lybrel, Seasonale and Nordette, when taken in a very specific way, though Plan B is more likely to be effective. To find out all of the birth control pills worldwide which can be used as emergency contraceptives, and how many of those pills to take, here is a very detailed list at Princeton's Emergency Contraception site, which is also the best site we know of for complete and current information on emergency contraception.
Want to see how effective Plan B may be in combination with another method of birth control you did use? If you used a method exactly as directed, look at the rate for combined perfect use. If you didn't use a method properly (for instance, you have missed some pills or only put a condom on halfway through intercourse) or that method failed (like a condom breaking or slipping off), look at the rate for typical use. Looking at these rates may help you figure out if and when Plan B will or won't likely make a big difference:
As well, the Copper-T IUD can also be inserted by a doctor for emergency contraception, as well as for continued use afterwards. Insertion of a Copper-T is more effective as EC than Plan B or using birth control pills -- only 1 in 1,000 women will become pregnant if an IUD is used as an emergency contraceptive -- and it may also be inserted as many as eight days after a risk, three days longer than Plan B may be effective. To use an IUD as EC, you'll need to schedule a visit with a sexual healthcare provider.
Check out the following links for more information about emergency contraception and for some questions and answers about EC:
Or, click on the tag for emergency contraception for a larger list.
When Good Birth Control Does Bad Things: EC is less likely to work the longer someone waits before taking it: it is MOST effective used within the first 24 hours. If a person takes it from 72-120 hours, it may still work, but is substantially less likely to. If taken after 120 hours -- while pregnancy may not occur just because it wasn't going to anyway -- it doesn't have a shot at working at all. It's a great idea if you're heterosexually active to have a pack or a prescription for Plan B on hand in advance: that way, if you ever need it, you can have it handy to take immediately.
Too, if a person throws up the pills (which is more likely to happen if you take them both, in the case of Plan B, at once) they aren't going to work.
The health risks presented by Plan B are similar to those of other oral contraceptives. While -- because they are not being used daily, but very rarely -- many women who can't use other hormonal contraceptives can usually use Plan B, do be sure to inform your pharmacist or healthcare provider about your medical history so they can be sure EC is safe for your use. Some common side effects with EC include: nausea, headaches, breast tenderness and irregular or unexplained vaginal bleeding or spotting.
If you are going to use EC or have used EC, do yourself -- and your sanity -- a favor and abstain from sexual intercourse for at least a few days. EC should not be considered to offer pregnancy prevention for sex which occurs while taking it or shortly thereafter taking it. Taking EC right after taking it again is likely to leave you feeling pretty cruddy and also pretty broke, so it's wise to put sex on the shelf while you deal with the current risk and come back to it after you have a little time to work through this. Obviously, if you are using EC because another method was not used, before coming to sex again which presents pregnancy risks, you'll want to assure that, for the next time, you do have a reliable method of birth control which will be used and which you have used long enough to be effective when we're talking about hormonal methods, or have had some practice with, such as barrier methods. If you intend to use condoms alone, you want to assure you know how to use them properly and that your partner intends to cooperate.
Plan B can be used as a backup method with ANY other form of contraception, but with some hormonal methods -- especially when a user is just starting them -- may pose or create extra side effects.
Don't forget: Statistically, sexually active young adults are as, if not more, likely to acquire a sexually transmitted infection (STI) as you are to become pregnant. Although 15-24-year-olds represent only one-quarter of the sexually active population, they account for nearly half of all new STIs each year, and of the 18.9 million new cases of STIs each year, 9.1 million (48%) occur among 15-24-year-olds (AGI). Often people have some funny ideas about who is most likely to get an STI, but the fact of the matter is that younger people -- of any sexual orientation, any economic class, any kind of relationship -- have been the highest risk group for some time now.
Condoms are the only method of birth control which also provide protection against STIs. It's pretty typical for younger people to ditch condoms if they have another method of birth control, so just remember that STIs are still a risk if you're using another method. You can read all about safer sex here -- Safe, Sound & Sexy: A Safer Sex How-To -- but the rule of thumb most medical experts and prevention organizations suggest, which we also encourage at Scarleteen is six months of safer sex, six months of sexual monogamy, and then TWO full STI screenings for each partner -- once at the start of that six months, once at the end -- before ditching latex barriers.