How Many Pills Until Emergency Contraceptive is Effective?

Emergency contraceptive pill

Emergency contraceptive pills are effective after taking the first dose, but it is recommended to take them as soon as possible after unprotected intercourse for maximum efficacy.

Mei, 10~19 year old female. Ask Date: 2015/08/03

Dr. Zhang Kunmin reply Obstetrics and Gynecology

Hello, the effects will be sufficient approximately one week after starting the medication.
Thank you! Wishing you peace and health.
Dr.
Zhang

Reply Date: 2015/08/03

More Info

Emergency contraceptive pills (ECPs), commonly referred to as "morning-after pills," are designed to prevent pregnancy after unprotected intercourse or contraceptive failure. The effectiveness of these pills depends on several factors, including the type of pill used, the timing of ingestion relative to intercourse, and individual physiological differences.

There are two main types of emergency contraceptive pills: those containing levonorgestrel (Plan B One-Step and its generics) and those containing ulipristal acetate (ella).
1. Levonorgestrel (Plan B One-Step): This type of emergency contraceptive is most effective when taken as soon as possible after unprotected intercourse. It is recommended to take a single dose of 1.5 mg within 72 hours (3 days) after the event. However, it can still be taken up to 5 days after intercourse, but its effectiveness decreases significantly with time. Studies indicate that taking the pill within 24 hours can reduce the risk of pregnancy by up to 95%, while taking it between 48 to 72 hours reduces effectiveness to about 89%.

2. Ulipristal Acetate (ella): This is a prescription-only emergency contraceptive that can be taken up to 120 hours (5 days) after unprotected intercourse. It is effective throughout this entire window, maintaining a consistent level of effectiveness regardless of when it is taken within that timeframe. The recommended dosage is a single 30 mg pill.

In terms of how many pills are needed for effectiveness, both types of emergency contraceptives are designed to be taken as a single dose. Taking more than the recommended dosage does not increase effectiveness and may lead to increased side effects, such as nausea, vomiting, and fatigue.
It's important to note that emergency contraceptive pills are not intended for regular use as a primary contraceptive method. They are a backup option and should be used as such. Regular contraceptive methods, such as birth control pills, IUDs, or condoms, are more effective for ongoing prevention of pregnancy.

If a person finds themselves needing emergency contraception frequently, it may be beneficial to consult with a healthcare provider to discuss more reliable long-term contraceptive options. Additionally, if there are concerns about potential pregnancy after taking emergency contraception, a follow-up pregnancy test is recommended about three weeks after the incident or as directed by a healthcare provider.

In summary, for emergency contraceptive pills, one pill is typically sufficient for effectiveness, provided it is taken within the appropriate time frame after unprotected intercourse. Always consult with a healthcare professional for personalized advice and recommendations regarding contraceptive options.

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