The Morning After Pill

Thinking about taking the Morning After Pill?

Get informed before you decide. 

What is the Morning-after Pill?

The morning-after pill is a type of emergency birth control (contraception). Emergency contraception is used to prevent pregnancy for women who've had unprotected sex or whose birth control method has failed.

The morning-after pill is intended for backup contraception only, not as a primary method of birth control. Morning-after pills contain either levonorgestrel (Plan B One-Step, Aftera, others) or ulipristal acetate (Ella).

Morning-after pills do not end a pregnancy that has implanted. They work primarily by delaying or preventing ovulation.

Levonorgestrel is available over-the-counter without a prescription; ulipristal acetate (Ella) is available only with a prescription.


Emergency contraception is an effective option for preventing pregnancy after unprotected sex, but it isn't as effective as other methods of contraception and isn't recommended for routine use. Also, the morning-after pill can fail even with correct use, and it offers no protection against sexually transmitted infections (STI's).

The morning-after pill isn't appropriate for everyone. Don't take a morning-after pill if:

  • You're allergic to any component of the morning-after pill

  • You're taking certain medications that can decrease the effectiveness of the morning-after pill, such as barbiturates or St. John's wort


If you're overweight or obese, there's some indication that the morning-after pill won't be as effective in preventing pregnancy as it is for women who aren't overweight.

Also, make sure you're not pregnant before using ulipristal (Ella). The effects of ulipristal on a developing baby are unknown. If you're breast-feeding, ulipristal isn't recommended.

Side effects of the morning-after pill, which typically last only a few days, might include:

  • Nausea or vomiting

  • Dizziness

  • Fatigue

  • Headache

  • Breast tenderness

  • Bleeding between periods or heavier menstrual bleeding

  • Lower abdominal pain or cramps


Levonorgestrel (Plan B One-Step) should be taken as soon as possible and less than 72 hours after unprotected sex.


Ulipristal (Ella) should be taken as soon as possible and less than 120 hours (5 days) after unprotected sex.

NOTE: The morning-after pill doesn't offer lasting protection from pregnancy. If you have unprotected sex in the days and weeks after taking the morning-after pill, you're at risk of becoming pregnant. 

Using the morning-after pill may delay your period by up to one week.

If you don't get your period within three to four weeks of taking the morning-after pill, take a pregnancy test.

If you should have bleeding or spotting that lasts longer than a week or develop severe lower abdominal pain three to five weeks after taking the morning-after pill, contact your health care provider. These symptoms can indicate a miscarriage or that the fertilized egg has implanted outside the uterus, usually in a fallopian tube (ectopic pregnancy).