What is this? 

Emergency contraception includes methods used to prevent pregnancy after sexual intercourse. These methods are recommended for use within 5 days, but they are most effective when used as soon as possible after intercourse. Emergency contraceptive pills prevent pregnancy by delaying or preventing ovulation and do not cause abortion. 

The three types of EC pills are: 

1. Ulipristal: This prescription-only medication affects progesterone to delay or prevent ovulation. It is effective for up to 5 days after unprotected sex without losing effectiveness and is more effective than progestin-only or combined EC pills.

2. Progestin-only EC: A single pill taken as soon as possible after unprotected sex. It works by stopping or delaying ovulation and is most effective within 3 days but moderately effective up to 5 days. Available over-the-counter for all ages, typically found in the family planning section.

3. Combined birth control pills: These contain both estrogen and progestin. When taken in higher doses, they can be used for emergency contraception within 5 days of unprotected sex by delaying ovulation. They are taken in two doses, with the number of pills varying by brand. Consult a healthcare professional or pharmacist for the correct dosage.

Some EC pills are available over the counter without a prescription, while others require one. The IUD must be inserted by an obstetrician–gynecologist (ob-gyn) or other health care professional.

How does this work?

Using EC does not cause an abortion. An abortion ends an existing pregnancy. EC prevents pregnancy from occurring. EC must be used soon after unprotected sexual intercourse to be effective. It does not work if pregnancy has already occurred.

Efficacy: 

The efficacy of emergency contraceptive pills (ECPs) varies based on the type of pill and the timing of administration:

1. Ulipristal Acetate (UPA) Pills:

• Effectiveness: Approximately 1.2% pregnancy rate.

• Timing: Most effective within 120 hours (5 days) after unprotected intercourse, especially between 72–120 hours.

2. Levonorgestrel (LNG) Pills:

• Effectiveness: Pregnancy rate ranges from 1.2% to 2.1%.

• Timing: Should be taken as soon as possible, ideally within 72 hours (3 days) but effective up to 120 hours after unprotected intercourse.

3. Combined Oral Contraceptives (COCs) as EC:

• Effectiveness: Varies, generally less effective than UPA and LNG.

• Timing: Should be taken as soon as possible within 120 hours after unprotected intercourse.

Key Points:

• Early Use: The sooner ECPs are taken after unprotected sex, the more effective they are.

• Type of Pill: UPA is more effective than LNG between 72–120 hours post-intercourse.

• No Effect on Established Pregnancy: ECPs do not interrupt an established pregnancy or harm a developing embryo.

Usage duration recommended: 

The emergency contraceptive pill (ECP) is most effective when used within three days (72 hours) after unprotected sex.