The morning after pill

How the morning-after pill works

Mary Smith
By Mary Smith. Updated: January 16, 2017
How the morning-after pill works

The morning-after pill was a revolutionary invention, that provoked both great opposition, as well as support. Today, we know that its effectiveness varies between 75% and 89 % according to the Department of Health and Human Services of the United States, but how does the morning-after pill work? When can it be taken? What are its effects? At we'll tell you all about them.

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  1. How the morning-after pill works
  2. When should you take the morning-after pill
  3. Side effects
  4. Warnings about taking the morning-after pill

How the morning-after pill works

The role of the emergency pill is to:

  • Prevent ovulation by delaying the process so that the egg can't be fertilised.
  • When the egg has already detached from the ovaries, the morning-after pill causes the cervical mucus to become thicker, preventing the passage of sperm to the egg.
  • However, it doesn't work when the egg has been fertilised, therefore it has no abortive properties. It's taken when regular contraceptive methods fail, for example, when a condom breaks, or in cases when you've had unprotected sex and fear a possible pregnancy.

Depending on the base compound, it may be administered from 24 to 120 hours after unprotected sex.

When should you take the morning-after pill

The morning-after pill on no account should be used as a regular contraceptive method. It's an emergency alternative that should be used only when another method of protection has failed, such as unprotected sex or in cases of rape.

Depending on the base compound, you can take it directly following sex and up to 72 hours afterwards, although the sooner you take it, the better its effect. If you've had unprotected sex and it's during your fertile days, it's recommended to take the morning-after pill as soon as possible.

Side effects

Depending on the compound of the morning-after pill, some of the side effects include:

  • Nausea
  • Vomiting
  • Headache
  • Bleeding not related to menstruation
  • Heavy bleeding during menstruation
  • Delay or advancement of the menstrual cycle
  • Patches on the skin

It's important that you read the instructions in the information leaflet before taking this type of emergency contraceptive pill, thus answering any questions you might have.

You'll know that the morning-after pill is taking effect when your period decreases accordingly. It's important to know that it can be a bit delayed.

Warnings about taking the morning-after pill

  • The first warning is that this method shouldn't be taken regularly because it could cause serious complications to your body. Remember that this is an emergency alternative.
  • Keep in mind that the effectiveness of the morning-after pill is much lower than that of other conventional methods such as the pill or condoms. Like any other oral contraception, it doesn't prevent the transmission of STDs, which can only be achieved with a condom.
  • The morning-after pill use isn't recommended if you have had breast cancer, or suffer from epilepsy, diabetes mellitus, severe hypertension, heart problems, among other conditions.

If you want to read similar articles to How the morning-after pill works, we recommend you visit our Sentimental relationships category.

  • Use this type of contraceptive method only in cases of emergency and remember that having sex requires being responsible and protecting yourself against unwanted pregnancy and against STDs in a healthy and mature manner

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How the morning-after pill works