Emergency Contraceptive Pill
The emergency contraceptive pill (ECP), also known as the morning-after pill, is a type of birth control that can be used after unprotected sex or when other forms of contraception have failed.
How it Works
The ECP works by preventing or delaying ovulation, which means that an egg is not released from the ovary. This prevents fertilization from occurring. If an egg has already been released, the ECP can also prevent a fertilized egg from implanting in the uterus.
Types of Emergency Contraceptive Pills
There are several types of ECPs available, including:
- Levonorgestrel (Plan B): This is a progestin-only pill that can be taken up to 72 hours after unprotected sex.
- Ulipristal acetate (ella): This is a selective progesterone receptor modulator that can be taken up to 120 hours after unprotected sex.
- Mifepristone: This is an antiprogestin pill that can be taken up to 120 hours after unprotected sex.
Efficacy
The efficacy of the ECP depends on the type of pill and how soon it is taken after unprotected sex. When taken as directed, the ECP can reduce the risk of pregnancy by:
- 89% if taken within 72 hours of unprotected sex (Levonorgestrel)
- 85% if taken within 120 hours of unprotected sex (Ulipristal acetate)
Side Effects
Common side effects of the ECP include:
- Nausea and vomiting
- Abdominal pain
- Fatigue
- Dizziness
- Headache
- Breast tenderness
Contraindications
The ECP is not recommended for women who:
- Are pregnant or suspect they may be pregnant
- Have a history of ectopic pregnancy
- Have a known allergy to the ingredients in the ECP
Availability
The ECP is available over-the-counter (OTC) at pharmacies and online, without a prescription, for women aged 17 and older. Women under the age of 17 require a prescription from a healthcare provider.
Frequently Asked Questions (FAQs)
What is an emergency contraceptive pill?
A medication taken to prevent pregnancy after unprotected sex.
How does it work?
It delays ovulation, preventing fertilization, or may affect implantation.
When should it be taken?
As soon as possible, ideally within 72 hours of unprotected sex.
Is it effective?
Generally, but effectiveness decreases over time after unprotected sex.
Are there different types?
Yes, including levonorgestrel and ulipristal acetate, with varying effectiveness.
Can anyone take it?
Most women, but certain medical conditions or medications may affect use.
Are there side effects?
Commonly, nausea, vomiting, and abdominal pain, among others.
Does it protect against STIs?
No, it only prevents pregnancy.
Can it be used as regular birth control?
Not recommended, due to lower effectiveness and potential side effects.
Is a prescription required?
Sometimes, depending on the type, location, and age of the user.
Article last updated on: 18th October 2025.
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