What You Should Know About Emergency Contraception Pills

It's a simple truth: Things don't always turn out the way you planned. Not all sexual encounters are anticipated, most people don't plan for pregnancy by way of a broken condom or a skipped birth control pill. That's where emergency contraception pills come in.

What Is Emergency Contraception?

Also called the morning-after pill, an emergency contraceptive pill is designed to help prevent pregnancy after birth control failure. It contains the active ingredient levonorgestrel, a synthetic form of the hormone progesterone (which is also in birth control pills in lower amounts). Levonorgestrel works in several ways, including the following:

• It prevents or delays ovulation, meaning your ovary does not release an egg.
• It thickens cervical mucous, making it more difficult for sperm to travel up the uterus toward a waiting egg.
• It thins the uterine lining, so a fertilized egg is less likely to implant.

Emergency contraceptives work best if taken within the first 24 hours of unprotected intercourse. It can still prevent pregnancy if taken within 72 hours. However, its effectiveness decreases with time, so the sooner you take it, the better.

Where Can I Get Emergency Contraception?

Currently, emergency contraception pills are legal in all 50 states, and no prescription is required. You can purchase them throughout the U.S. at most pharmacies, large retailers and grocery stores. Family planning clinics also offer levonorgestrel, along with personalized counseling and advice. Although it's available for online purchase from many vendors, time is of the essence with emergency contraceptives, so choose a store that provides pick-up or next-day shipping to avoid a delay in receiving your dose.

Note that some states allow pharmacists and other medical providers to refuse to dispense emergency contraception pills based on personal beliefs, as noted by the American College of Obstetricians and Gynecologists. Some locations may also have age restrictions that prevent minors from receiving emergency contraceptives without parental or guardian consent.

The Fine Print

For future reference, keep the following in mind:

• Emergency contraceptives may be less effective in women who are overweight or obese, so speak with your provider if you're concerned that your weight may make it less effective.
• You will likely notice changes in your first menstrual cycle after taking emergency contraceptives. This pill may cause nausea, vomiting, fatigue and headache, but these symptoms should be temporary.
• Emergency contraceptives will not terminate a pregnancy that is already implanted in the uterus.
• Individuals who take certain antibiotics, antifungal medications, antiviral medications, seizure medications or the supplement St. John's Wort should not take emergency contraceptives to avoid interactions. (This list is not all-inclusive. Check with your doctor or pharmacist to determine if there are any interactions with the medications and/or supplements you're currently taking.)
• Emergency contraceptives are not a substitute for proactive contraception. It is more costly and less effective than other birth control methods and does not protect against sexually transmitted infections.

Are There Alternative Emergency Contraceptives?

Ulipristal acetate, another emergency contraceptive, works similarly to the standard morning-after pill. This medication may be taken up to five days after unprotected intercourse — but the sooner it's taken, the more likely it'll prevent pregnancy. However, it is available by prescription only.

Additionally, if you are not already on a reliable form of birth control, a copper IUD placed within five days of unprotected sex can serve as emergency contraception while also providing long-acting pregnancy protection.

Knowing Your Options

When used correctly and promptly, emergency contraception pills are a safe and effective way to help prevent pregnancy after birth control failure or unprotected sex. Even if you never end up using emergency contraceptives, knowing they're an option can offer peace of mind. Being informed about emergency contraception is vital for making responsible decisions regarding your sexual health.

Clinically reviewed on Sept. 3, 2024.