Emergency Contraception

Common questions about Ella (ulipristal), Plan B (levonorgestrel) and the Copper IUD.

General Questions

How does emergency contraception work?

Emergency contraception primarily works by delaying or preventing ovulation, which means it stops the egg from being released from the ovary. It may also change the lining of the uterus, making it less likely for a pregnancy to occur. EC is not an abortion pill and won't affect an existing pregnancy.

Why do TeleTest physicians prefer Ella?

Ella, known as Ulipristal acetate, is often the preferred choice for emergency contraception. Its higher efficacy stands out when compared to Plan B. Clinical studies highlight that Ella tends to have a lower failure rate, typically ranging from about 0.9% to 2.1%. This is in contrast to Levonorgestrel-based emergency contraceptives, where the observed pregnancy rates in trials span a slightly wider range.

What particularly sets Ella apart is its remarkable performance in the crucial hours following unprotected sex. Studies show that its effectiveness in reducing the chances of pregnancy is significantly higher than Levonorgestrel, particularly within the first 24 to 72 hours after intercourse. This enhanced efficacy in the critical initial period post-exposure makes Ella a highly reliable choice for emergency contraception.

Are there different types of emergency contraception available?

Yes, there are mainly two types: emergency contraceptive pills (ECPs) and the copper intrauterine device (IUD). ECPs come in two forms, one containing levonorgestrel (Plan B) and the other ulipristal acetate (Ella). The copper IUD is inserted by a healthcare provider.

What is the most effective type of emergency contraception?

The copper IUD is the most effective form, reducing the risk of pregnancy by more than 99%. Of the pills, ulipristal acetate is slightly more effective than levonorgestrel, especially if taken later within the 5-day window after unprotected sex. You require a visit to a local sexual health clinic to insert a copper IUD, as these cannot be inserted by a pharmacist in Ontario.

How soon should emergency contraception be taken after unprotected sex?

The sooner, the better. ECPs are more effective the sooner they are taken. Ideally, levonorgestrel pills should be taken within 72 hours, and ulipristal acetate pills within 120 hours. The copper IUD can be inserted up to 5 days after unprotected sex.

Can emergency contraception be used as a regular form of birth control?

No, emergency contraception is not meant for regular use. It's less effective than regular contraceptive methods and doesn't protect against sexually transmitted infections. It's designed for occasional use, like in cases of unprotected sex or contraceptive failure.

Are there any side effects of taking emergency contraception?

Some women may experience side effects like nausea, tiredness, headache, breast tenderness, or changes in their next period. These side effects are usually mild and short-term. If you have severe abdominal pain after taking EC, it's important to contact a healthcare provider.

How does body weight affect the efficacy of emergency contraception?

Body weight can impact the effectiveness of emergency contraceptive pills. Higher body weight, particularly a BMI over 35, might reduce the effectiveness of these pills. The copper IUD's effectiveness is not affected by body weight.

Is emergency contraception safe for all women to use?

Emergency contraception is safe for almost all women. However, certain health conditions may influence the type of EC that is recommended.

Can emergency contraception cause an abortion?

No, emergency contraception does not cause abortion. It works by preventing or delaying ovulation or by preventing fertilization. It won't terminate an existing pregnancy.

Is emergency contraception effective if taken during ovulation?

Its effectiveness can be reduced if ovulation has already occurred. ECPs work best when taken before ovulation.

Does emergency contraception protect against sexually transmitted infections (STIs)?

No, EC does not protect against STIs. Using condoms is the best way to protect against STIs.

Can emergency contraception fail? If so, why?

Yes, while effective, EC is not foolproof. It can fail if taken too late, if ovulation has already occurred, or due to individual factors like body weight or interactions with other medications.

What should I do if I vomit after taking emergency contraception?

If vomiting occurs within two hours of taking an EC pill, it may not be effective. In such a case, another dose should be taken as soon as possible. If you're prone to nausea, speak with a healthcare provider about options.


How is Ella taken?

Ella is taken as a single oral tablet. The tablet should be taken as soon as possible after unprotected sex, but it can be effective if taken up to 120 hours (5 days) afterward. It's important to take the tablet whole, with water, and not to crush or chew it.

How effective is Ella compared to other emergency contraceptives?

Ella is known to be effective up to 120 hours (5 days) after unprotected sex. Studies have shown it maintains its efficacy better over this period compared to levonorgestrel-based emergency contraceptives.

Does Ella's effectiveness change based on the timing of usage?

The effectiveness of Ella (ulipristal acetate) as an emergency contraceptive does vary slightly depending on when it is taken after unprotected sex. Its highest efficacy is observed when taken immediately or within a short time after the incident. As time extends towards the 120-hour (5-day) mark, its effectiveness can decrease. However, Ella is distinctively effective even on the fifth day, maintaining a higher efficacy compared to other emergency contraceptives like levonorgestrel-based pills, which generally decrease in effectiveness more significantly over time. It's important to note that while Ella can be taken up to 5 days after unprotected sex, taking it as soon as possible is always recommended for optimal effectiveness.

Can Ella be used by women of all weights?

Ella (ulipristal acetate) is generally considered effective for women of various weights. However, there is some evidence suggesting that its effectiveness may be reduced in women with a higher body mass index (BMI). Ella (ulipristal acetate) is most effective for individuals with a Body Mass Index (BMI) of 30 or less. It is considered not effective for those who have a BMI of 35 or more.`

Do certain medications affect Ella's effectiveness?

Ella, an emergency contraceptive, can have its effectiveness reduced by certain medications and supplements. These include the antibiotic Rifampin, the antifungal Griseofulvin, specific HIV medicines, some anti-seizure medications used also for psychiatric conditions, and the herb St. John's Wort. It's crucial for individuals taking any of these substances to consult with a healthcare professional before using Ella.

Plan B

What is Plan B?

Plan B One-Step is an emergency contraceptive pill that helps prevent pregnancy after unprotected sex or birth control failure. It contains levonorgestrel, a hormone used in many birth control pills.

How does Plan B work?

Plan B works primarily by temporarily delaying ovulation, meaning it stops the release of an egg from the ovary.

How effective is Plan B?

When taken within 72 hours after unprotected sex, Plan B can reduce the chance of pregnancy by 75-89%. It's most effective the sooner it's taken after unprotected sex.

What if I’m already pregnant and I take Plan B?

Plan B will not work if you are already pregnant and it does not harm an existing pregnancy. It is not an abortion pill.

What are the side effects of Plan B?

Some women may experience side effects like changes in their period (lighter, heavier, early, or late), nausea, abdominal cramps, tiredness, headache, dizziness, breast tenderness, or vomiting.

Do certain medications affect Plan B's effectiveness?

Yes, certain medications such as some antibiotics, antifungals, HIV medicines, anti-seizure medicines, and St. John’s Wort can decrease the effectiveness of Plan B.

Other Common Questions

How does emergency contraception affect my menstrual cycle?

Emergency contraception may cause your next period to be earlier, later, or more painful than usual. These changes are generally temporary.

Can I use emergency contraception if I am breastfeeding?

Yes, you can use emergency contraception while breastfeeding. It's generally considered safe, and most types don't affect milk supply.

Can I take emergency contraception more than once in a menstrual cycle?

Yes, absolutely. While it's possible to use emergency contraception more than once in a cycle, it's not recommended as a regular method of birth control. Repeated use can lead to menstrual irregularities and is less effective than ongoing contraceptive methods.

How do I know if emergency contraception has worked?

The primary indication that emergency contraception has worked is the arrival of your next menstrual period. If your period is more than a week late, it's advisable to take a pregnancy test.

What are the long-term effects of using emergency contraception?

Emergency contraception has no known long-term effects on health or fertility. It's a safe option when used as directed in emergencies.


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