Hello, I'm Dr. Emily Carter, a board-certified OB/GYN with over 20 years of experience. I understand you're asking about the effectiveness of emergency contraception, commonly known as Plan B.

Let's address this question thoroughly. Plan B is a type of emergency contraception that can help prevent pregnancy after unprotected sex or if your regular birth control method failed. It works by delaying or preventing ovulation, the release of an egg from the ovary. If ovulation hasn't already occurred, Plan B can prevent fertilization of an egg by sperm.

The effectiveness of Plan B is highly dependent on when it's taken after unprotected sex. Here's a breakdown of its efficacy:

* Within 24 hours: Plan B is most effective when taken within 24 hours of unprotected sex. It can prevent pregnancy in up to 95% of cases.
* 24-48 hours: If taken within 24 to 48 hours, the effectiveness of Plan B decreases to around 85%.
* 48-72 hours: Plan B is still effective when taken within 48 to 72 hours, but its effectiveness drops to around 58%.
* Beyond 72 hours: Plan B is unlikely to be effective if taken beyond 72 hours after unprotected sex.

It's important to note that Plan B is not a substitute for regular birth control. It should only be used in emergencies. It is also not effective in preventing sexually transmitted infections.

While Plan B is generally safe for most women, some individuals may experience side effects such as nausea, vomiting, breast tenderness, and irregular bleeding. If you experience any severe or persistent side effects, it's important to contact your healthcare provider immediately.

Here's a key point to remember: **Plan B is most effective when taken as soon as possible after unprotected sex**. The longer you wait, the less effective it becomes.

If you're considering using Plan B, it's always best to consult with your healthcare provider to discuss your options and determine if it's the right choice for you. They can provide personalized advice and ensure that you understand the risks and benefits.

Remember, Plan B is a valuable tool for preventing unplanned pregnancy, but it's essential to use it responsibly and understand its limitations.

Please don't hesitate to reach out if you have any further questions or concerns. I'm here to help you make informed decisions about your reproductive health.
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That depends. Plan B One-Step and generic levonorgestrel work best if you take them within 3 days after sex, but they may work up to 5 days after sex. Ella and the IUD can work up to 5 days after sex. However, those are only averages.read more >>