How Effective Is Plan B After 4 Days?
What is Plan B?
Plan B is an emergency contraceptive pill for women, it contains 1.5 mg of levonorgestrel—an ingredient that is also commonly found in birth control pills. Plan B can prevent pregnancy when people have sex without contraception. Plan B does not end an already established pregnancy and does not protect against sexually transmitted infections (STIs).
How does Plan B work?
If taken within 72 hours of unprotected sex or following a contraceptive accident, Plan B works by:
- Stopping ovulation temporarily
- Preventing fertilization
- Preventing implantation
Unlike regular birth control methods, which are used before or during sex, Plan B is used to prevent pregnancy after unprotected sex or following a contraceptive accident.
Plan B comes in a one-pill dose (levonorgestrel 1.5 mg). If taken within 72 hours (three days) and preferably within 12 hours of a contraceptive accident or unprotected sex, Plan B® can prevent pregnancy.
How Effective Is Plan B After 4 Days
If taken within 3 days (72 hours) of unprotected sex, Plan B can reduce the chance of pregnancy by 75 to 89 percent. According to Plan B’s manufacturer, the sooner you take the pill, the more effective it is.
However, there is a scarcity of data on the effectiveness of Plan B after 4 days. Nevertheless, studies suggest that once ingested, Plan B can be effective for up to a maximum of five days. After this amount of time, the hormones that were in the pill will have left the body.
Research has found that Plan B is “moderately effective” when taken between 72 and 120 hours after sex. But remember that its effectiveness decreases the longer you wait.
How do I use Plan B morning-after pills?
Take Plan B morning-after pills as soon as you can after unprotected sex. Simply swallow the tablet the way you would any other pill. Read the instructions that come in the package for more information.
You can take Plan B up to five days after unprotected sex, but they work much better if you take them during the first three days.
Take a pregnancy test if you haven’t gotten your period within three weeks after taking the morning-after pill.
Take Plan B One-Step morning-after pill if:
• You didn’t use any birth control.
• The condom came off or broke.
• The diaphragm slipped out of place.
• You missed at least two or three active birth control pills in a row.
• You forgot to insert your ring or apply your patch.
• Your partner didn’t pull out in time.
• You have another reason to think your birth control might not have worked.
• You were forced to have unprotected sex.
Remember: Plan B will not protect you from getting pregnant if you have unprotected sex after taking it. To protect you against getting pregnant, you need to take it right after you have unprotected sex and use a form of contraception when you have sex
Do not take Plan B if:
• You know you are pregnant or suspect you might be.
• You have a history of allergy or hypersensitivity to its ingredients.
• You have a history of recent abnormal vaginal bleeding that your doctor has not yet evaluated.
What Drugs can affect the effectiveness of Plan B?
Certain medications can alter the effectiveness of Plan B.
If you take any of the following, speak with a healthcare professional before buying Plan B:
• rifampin (an antibiotic)
• griseofulvin (an antifungal)
• St. John’s wort (an herb)
• seizure medications, including carbamazepine, phenobarbital, and primidone
• some HIV medications, including efavirenz
Although the manufacturers advise taking Plan B within 3 days of unprotected sex, you can take it up to 5 days after penis-in-vagina sex.
Does the Plan B morning-after pill have side effects?
Plan B One-Step can cause side effects for some people. According to the FDA, some reported side effects include:
• breast tenderness
• dizziness
• fatigue
• headache
• late period
• lower abdominal pain
• menstrual bleeding that is heavier than usual
• nausea
The most common side effect of Plan B One-Step is heavier menstrual bleeding. Otherwise, the FDA generally regards the medication as safe. In addition, People who are breastfeeding, or chestfeeding, can use the medication without adverse effects.