There isn’t a limit to how many times you’re free to use theemergency contraceptivepill Plan B.
Plan B, the morning-after pill, prevents pregnancy after unprotected sex.
It mainly works by preventing or delayingovulation(egg release from an ovary).
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It may also help prevent pregnancy by thickening the cervical mucus and blocking sperm movement to the egg.
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How Effective Is Plan B?
Plan B is most effective when it’s taken as soon as possible after unprotected intercourse.
For it to work, it must be taken within 96 hours (four days) of sex.
The effectiveness of Plan B decreases over time.
Effectiveness also depends on the timing of the menstrual cycle.
The older version of Plan B contained two 0.75 mg levonorgestrel tablets to be taken twelve hours apart.
This two-step product is no longer available in the United States.
If vomiting occurs within three hours of taking Plan B, you should take another Plan B pill.
How Long Does Plan B Take to Work?
Plan B starts to work quickly.
On average, it reaches the highest concentration in the body within about two hours.
What Are Other Birth Control Methods?
Birth control methods include emergency contraceptives and regular (ongoing) methods.
There are manyoptionsdepending on your needs and lifestyle.
Otheremergency birth control methodsavailable in the United States include intrauterine devices and the tablet Ella (ulipristal acetate).
However, they may be used off-label.
A healthcare provider must place these IUDs into the uterus within five days of unprotected sex.
The primary way copper IUDs work by impacting sperm movement.
This prevents the egg from being fertilized.
A healthcare provider must place it in the uterus within five days of unprotected sex.
It works similarly to Plan B, preventing or delaying ovulation.
It is available only by prescription and can be taken up to five days after unprotected sex.
Ulipristal acetate is more effective than Plan B.
The pregnancy rate for people who use this product is 0.9% to 1.8%.
Ulipristal acetate is affected by body weight, but not to the extent that Plan B is.
About 3% of people will get pregnant after using the Yuzpe method.
What Is the Most Effective Birth Control Method?
It is most effective right after unprotected sex, and its effectiveness decreases over time.
It won’t work if it’s taken more than four or five days after intercourse.
Several medicines, including some used for epilepsy, lower the effectiveness of Plan B.
It’s best for people with a BMI less than 25 and less effective for people with higher BMIs.
Other options for emergency birth control are more effective, but they also have more barriers to use.
These include copper and hormonal IUDs and the prescription Ella.
Frequently Asked Questions
you’re able to take Plan B as often as you need it.
Plan B works within three hours of taking it.
The copper IUD is the most effective emergency birth control method.
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