Should I Take a Pregnancy Test After Plan B?

You had unprotected sex and took Plan B, and now you’re on pins and needles, wondering if it worked.

Being unsure if Plan B successfully prevented a pregnancy or not can be really nerve-racking. So should you take a pregnancy test after taking Plan B?

We’ll answer that and your other questions here.


About Plan B

Plan B One-Step is the brand name of a morning-after pill that women take to prevent pregnancy after contraception failure or unprotected sex that is consensual or forced. It’s not the same as the abortion pill, which ends a confirmed pregnancy.

Plan B is available at local stores without a prescription and doesn’t require identification or proof of age to purchase. It is most effective at preventing pregnancy 12-24 hours after unprotected sex. According to the manufacturer, it’s approximately 61% effective if taken between 48 and 72 hours (2-3 days). The sooner it’s taken, the more effective it is.

Plan B contains high levels of hormones and is not intended to be used as regular birth control.


What Happens After You Take Plan B?

If you choose to take Plan B, it may prevent pregnancy in one of three ways:

  • Preventing ovulation
  • Delaying ovulation
  • Preventing implantation of a fertilized egg into the uterine lining

Side effects do accompany Plan B. Once you take it, you can experience:

  • Breast tenderness
  • Cramps
  • Dizziness
  • Fatigue
  • Headache
  • Nausea/vomiting
  • Vaginal bleeding

Should You Take a Pregnancy Test After Plan B?

The short answer about whether you should take a pregnancy test or not after taking Plan B is, “It depends.”

No matter what, a pregnancy test will not detect a pregnancy until a minimum of ten days after conception, so wait at least that amount of time. It’s best to wait no less than two weeks after conception to reduce your risk of a false-negative test result.

If your next period after taking Plan B is normal, and you don’t have pregnancy symptoms, you don’t need to take a pregnancy test.

However, you should take a pregnancy test after Plan B if:

  • You miss your next period.

If you don’t get your next period, take a pregnancy test. It’s common for your next period to be a few days early or late after taking Plan B. Keep in mind that bleeding within a few days of taking Plan B is not a period, so don’t count it as one.

Also, don’t count spotting as a regular period. Sometimes, women experience implantation bleeding when they are pregnant and think it’s a light period. This misunderstanding can delay a pregnancy diagnosis.

  • You’re experiencing pregnancy symptoms.

Plan B side effects can mimic pregnancy symptoms when you aren’t pregnant. But if you have pregnancy symptoms and suspect you might be pregnant despite getting a period, go ahead and take a pregnancy test.

  • You need peace of mind.

Sometimes, you simply need a little peace of mind. And that’s a valid reason to take a pregnancy test!


Get Your Pregnancy Test

Fort Worth Pregnancy Center offers confidential pregnancy services, including pregnancy testing, at no cost to you. Our lab-quality tests can detect a pregnancy within ten days of conception.

Contact us today for an appointment with one of our caring professionals, and get the answers you deserve. You can also call or text us at 817-924-9110 or email us at



Cleveland Clinic Staff. (2019, February 19). Ovulation, conception & getting pregnant. Cleveland Clinic.–getting-pregnant.

Goldman, R. (2018, November 12). What is implantation bleeding? Healthline.

Mayo Clinic Staff. (2020, June 19). Morning-after pill. Mayo Clinic.