What are My Chances of Pregnancy with Plan B?

There are several things that factor into a woman’s chance of being pregnant. Her age, where she was in her cycle during intercourse, whether ejaculation occurred, whether there was any pre-ejaculation that occurred, and whether any forms of birth control or emergency birth control were used.

TeenHealthFX is unable to speak about all of these factors given the limited information we have, but we can give you information on the effectiveness of Plan B. Planned Parenthood provides the following information about the effectiveness of Plan B:

• Levonogestrel pills, including the brands Plan B One-Step and Next Choice One Dose, are up to 89 percent effective when taken within 72 hours (three days) after unprotected sex. They continue to reduce the risk of pregnancy up to 120 hours (five days) after unprotected sex, but they are less effective as time passes.
• The morning-after pill will not prevent pregnancy for any unprotected sex you may have after taking the pills.
• Levonogestrel pills may not work as well if your Body Mass Index (BMI) is more than 25. The IUD or ella are better options if you're overweight and need emergency contraception.

The odds of your being pregnant are significantly reduced given that your boyfriend did not ejaculate inside of you and you took Plan B within 72 hours of having unprotected sex. However, FX cannot give you an exact number as to the odds.

If your period does not come as expected, then FX recommends that you take a pregnancy test and/or meet with a doctor to find out if you are pregnant. Even if you are not pregnant, FX recommends you meet with a doctor to discuss birth control options if you plan to continue to be sexually active so you can significantly reduce the chance of these kinds of scares in the future. Doctors generally recommends that sexually active teens and young adults use a condom each and every time they have sex to protect against unwanted pregnancies and the transmission of STDs, as well as a back-up method of birth control such as the pill or birth control shot as added protection against unwanted pregnancies. But your doctor will be able to recommend the best method for you.

FX would also recommend that you and your boyfriend check out the links in our Resource of the Month: Planned Parenthood Resources on Safer Sex. Here you will find links to information on sexual readiness, how pregnancy happens, birth control, STDs, pregnancy tests, emergency contraception and more. The more educated the two of you are, the greater the chances you will both make healthy decisions when it comes to sexual health issues.

If you don't have a doctor and live in northern New Jersey, you can call the Adolescent/Young Adult Center for Health at 973-971-5199 for an appointment with an adolescent medicine specialist or contact your local teen health center or Planned Parenthood. You can also contact your insurance company for a list of in-network providers.