Plan B & Other Emergency Contraceptives


Emergency contraceptives, which are a form of birth control, are referred to by many names including the morning-after pill, “the pill”, Levonogestrel pill, Plan B One-Step®, Next Choice One Dose®, My Way®, EContra® EZ, Take Action®,  and Ella®.  They are not the same as RU486 (the abortion pill).

The purpose of emergency contraception is to prevent pregnancy after unprotected sex, or after the birth control method has failed.  Most methods must be taken within the first 72 hours after unprotected sex.

How it works:

Emergency contraception works in one of three ways, depending on when it is taken after unprotected sex and where you are in your cycle: [1]

  1. Prevent ovulation (the egg will not be released from the ovary)
  2. Inhibit fertilization (affect the lining of the fallopian tubes so that sperm cannot reach the egg)
  3. Inhibit implantation of the fertilized egg ( irritate the lining of the uterus so that it’s harder for the embryo to implant in the uterus)

The 3rd way that emergency contraception works is one that many people are not aware of.  While it only happens on rare occasions, here’s what you need to know about this possibility:

Fertilization, the moment when an individual child with its own DNA is formed, takes place in the fallopian tube. The fetus then travels down the fallopian tube to the uterus, where he or she attaches to the womb lining to receive nourishment and continue growing and developing. This process, the fetus traveling from the fallopian tube to the womb, can take 5-7 days. During that time, emergency contraception could prevent the fetus from attaching to the uterus lining, thus ending the fetus’s life due to a lack of nourishment.

Side Effects:

There are several short-term side effects with emergency contraception, including:

  • Nausea, diarrhea, or stomach pain
  • Cramping & abdominal pain
  • Bleeding
  • Fatigue
  • Headache
  • Dizziness
  • Breast tenderness
  • Hiding an ectopic pregnancy

If you experience severe abdominal pain, you may have an ectopic pregnancy (outside the uterus) and should get immediate medical attention.

Emergency contraception may cause your next period to be heavier or lighter than usual. It may also come earlier or later than is normal for you. If your period is more than a week late, get a pregnancy test to make sure you’re not pregnant. [2]


If you take it within 72 hours after you’ve had unprotected sex, emergency contraception can reduce the risk of pregnancy by up to 89%. If you take emergency contraception within 24 hours, it is about 95% effective. [3]

If you weigh over 165 lbs, emergency contraception is significantly less effective, about 3 times more likely to fail.  For obese women with a BMI of 26 or over, clinical studies show that pregnancy rates may be no different than if no emergency contraception was used.  [4]

Note: Emergency contraception will not protect against any STD’s or STI’s (sexually transmitted diseases or infections), including HIV and AIDS.

Before taking emergency contraception:

  • Do not use Plan B if you are already pregnant. Plan B will not terminate a pregnancy after the fertilized egg has attached to the uterus.
  • Find out if you have an allergy or hypersensitivity to its ingredients. It’s also a good idea to ask your doctor about possible interactions with other medications you are taking. [5]
  • Take a pregnancy test. If you have an ectopic pregnancy (when the fertilized egg implants outside of the uterus), emergency contraception won’t end the pregnancy, and the normal bleeding and cramping may mask the symptoms of an ectopic pregnancy.  An ectopic pregnancy is a medical emergency.

Emergency Contraception & Ectopic Pregnancy:

The cramping & abdominal pain that may result from taking emergency contraception can mask the symptoms of an ectopic pregnancy, which requires emergency care.   Call your doctor right away if you have severe pain in your lower stomach or side. This could be a sign of an ectopic pregnancy (a pregnancy that implants outside of the uterus). An ectopic pregnancy is a medical emergency.

To reduce this risk, get a pregnancy test before taking emergency contraception.  Life Options can provide you with a free pregnancy test, as well as an opportunity to speak with a medical professional and ask any questions you may have.  Besides, if you’re already pregnant, there’s no need to take emergency contraception, and Life Options can provide help and options in an unplanned pregnancy.


Your Next Step:

Make an Appointment