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Emergency Contraceptive Pill aka the Morning After Pill: The Mechanism, Use and Considerations

Unplanned or unprotected sex can occur, despite our best efforts to prevent it. In such situations, emergency contraception, commonly referred to as the morning-after pill, can serve as a crucial emergency solution to prevent unintended pregnancies. This article aims to provide a comprehensive overview of the emergency contraception pill, including its mechanism of action, usage, availability, and important considerations.

By understanding the pros and cons of emergency contraception, individuals can make informed decisions, and prioritize the use of regular contraception for long-term pregnancy prevention.

How Emergency Contraceptive Pill (ECP) Works

Emergency contraception pill primarily works by disrupting or delaying ovulation (the release of an egg from the ovary), which could have resulted in pregnancy due to unprotected sex or contraceptive failure.

There are two main types of ECPs:

1. Levonorgestrel-containing pills:

These contain a synthetic hormone called levonorgestrel, which is a progestin (a synthetic hormone that mimics the natural hormone called progesterone in the body). Levonorgestrel inhibits or delays ovulation, thus preventing the release of an egg from the ovary, and therefore an unintended pregnancy in case unprotected sex or contraceptive failure occurs.

They are divided into two types:

Levonorgestrel containing ECP with one pill: This type of ECP contains a single pill, typically with 1.5 milligrams of Levonorgestrel. It is generally taken as a single dose orally and is commonly available at a pharmacy without a prescription.

Levonorgestrel containing ECP with two pills: This type of ECP consists of two pills, each typically containing 0.75 milligrams of Levonorgestrel. The pills are taken in two separate doses, usually 12 hours apart, within 72 hours after unprotected sex or a contraceptive failure has occurred.

2. Ulipristal acetate containing ECP:

Ulipristal acetate is a selective progesterone receptor modulator, which means it works by blocking the effects of natural progesterone, a hormone necessary for ovulation. Therefore, in case unprotected sex or a contraceptive failure has occurred, it prevents an unintended pregnancy by preventing or delaying ovulation. However, this pill is not available in India.

Effectiveness of Emergency Contraceptive Pill

The effectiveness of emergency contraception varies depending on the timing of its administration. It is most effective when taken as soon as possible after unprotected sex. According to the American College of Obstetricians and Gynecologists (ACOG), levonorgestrel-based emergency contraception can reduce the risk of pregnancy by 75-89% when taken within 72 hours of unprotected sex.

It's important to note that emergency contraception is not 100% effective. The later it is taken after unprotected sex, the higher the likelihood of a pregnancy. Therefore, it is crucial to take an ECP as soon as possible after unprotected sex or contraceptive failure has occurred.

Proper Use of Emergency Contraceptive Pill

Levonorgestrel-based pills are available over the counter without a prescription in a pharmacy and typically involve taking one or two pills, depending on the brand. To ensure the maximum effectiveness of ECP, it is important to understand and follow the recommended usage guidelines:

Take it as soon as possible: Levonorgestrel ECPs are most effective when taken as soon as possible after unprotected sex. The sooner you take it, the better chance it has of preventing pregnancy, i.e. within 72 hours after unprotected sex or a contraceptive failure has occurred.

Follow the recommended dosage: Read the instructions provided with the specific brand of Levonorgestrel ECP you have. A single pill containing 1.5 milligrams of Levonorgestrel is taken orally as a single dose, whereas Levonorgestrel containing ECP with two pills have 0.75 milligrams of Levonorgestrel each and are administered orally as two doses. Both kinds of pills must be taken within 72 hours after unprotected sex or a contraceptive failure to avoid an unintended pregnancy.

Take the pill with water: Swallow the pill whole with a glass of water. Avoid chewing or crushing it.

Take it regardless of the time of day: Levonorgestrel ECPs can be taken at any time during the day, with or without food.

Repeat dosage if needed: In some cases, a second pill of Levonorgestrel ECP, whether one-pill or two-pill-based, may be recommended if vomiting occurs within two hours of taking the first dose. Consult the instructions or a doctor for guidance on repeating the dosage.

It is advisable to carefully read and follow the instructions provided with the medication. If there are any doubts or questions, consulting a doctor is recommended.

Remember, emergency contraception should not be used as a regular form of contraception, as it is designed for occasional use as a backup option.

Availability and Accessibility

ECPs are widely available in pharmacies, clinics, and family planning centers. Levonorgestrel-containing ECP is accessible without a prescription. This ensures that people can obtain emergency contraception quickly, allowing for prompt action when needed.

The Pros of Emergency Contraception Pill

ECP offers several advantages that make it a valuable option after unprotected sex or contraceptive failure has occurred:

a. Timely Solution: ECP provides a second chance to prevent unintended pregnancies, offering peace of mind during a stressful situation.

b. Accessibility and Availability: Levonorgestrel-containing ECP is readily accessible without a prescription, ensuring convenient availability when needed.

c. Confidentiality: ECP can be obtained discreetly, respecting the privacy and confidentiality of those seeking it.

Considerations and Limitations

While ECP serves as an important backup option, there are considerations and limitations to keep in mind:

a. Reduced Effectiveness over Time: The effectiveness of ECP decreases with time the later it is taken after unprotected sex has occurred. After 72 hours, the effectiveness of levonorgestrel-based ECP decreases significantly. Therefore, taking it as soon as possible is crucial.

b. Side Effects: Some individuals may experience mild side effects after taking an ECP, such as nausea, vomiting, breast tenderness, or irregular menstrual bleeding. These side effects are typically temporary and resolve on their own.

c. No Protection Against STIs: ECP does not protect against sexually transmitted infections (STIs). To ensure comprehensive protection, using a condom is necessary.

d. Not a Substitute for Regular Contraception: While the emergency contraceptive pill provides a safety net, it should not replace regular contraceptive methods. Regular contraception, such as oral contraceptives, injections, implants, or intrauterine devices (IUDs), offers more reliable and continuous protection against unintended pregnancies.


Understanding its mechanism, proper usage, and availability is crucial for individuals seeking an emergency solution to prevent unintended pregnancies.

While ECP offers benefits such as timeliness and accessibility, it is essential to acknowledge its limitations and consider it as a backup option rather than a primary method of contraception.

By using regular contraception and practicing safe sex, individuals can take proactive steps to prevent unintended pregnancies.



  • American College of Obstetricians and Gynecologists (ACOG). Emergency Contraception. Retrieved from:

  • Planned Parenthood. Emergency Contraception. Retrieved from:

  • Centers for Disease Control and Prevention (CDC). Emergency Contraception. Retrieved from:


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