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Can I Take Plan B After a Positive Pregnancy Test?

Writer: Mosaic Health
Mosaic Health
Sep 15
2 min read

This is one of the most common questions we hear. We’ll walk through what Plan B is, what it can and cannot do, and what your next best step should be if you’ve gotten a positive result.

Plan b pill on a yellow background

What Is Plan B?

Plan B One-Step® (also called the “morning-after pill”) is a type of emergency contraception. It’s designed to help prevent pregnancy after unprotected sex or birth control failure (like a broken condom). Plan B is most often taken within 24 hours of sexual intercourse. Side effects vary from person to person, and you should speak to a medical professional about your health history and potential risks.


Can Plan B Work After a Positive Pregnancy Test?

No. Plan B will not work after a positive pregnancy test, and it is not safe to take.

A positive pregnancy test means your body is already producing pregnancy hormones (hCG), which typically happens after implantation and human development has begun. 


Why Did I Test Positive So Soon?

A pregnancy test can become positive earlier than many people expect. Some reasons include:

  • You ovulated earlier than you thought

  • Your cycle is irregular

  • You conceived from sex that happened earlier than you assumed

  • The test is detecting pregnancy from implantation that already occurred


Even if it’s only been a short time, a test can be accurate—especially if it’s taken after a missed period.


What If I’m Not Sure When I Conceived?

That is completely normal. Ovulation doesn’t always happen on the same day each cycle, and sperm can live inside the body for up to 5 days.


That’s why an ultrasound can be one of the most reliable ways to get clarity and avoid guessing.



What Should I Do If I Have a Positive Test?

If your test is positive, your next step should be to confirm the pregnancy and learn how far along you are. Start with:

1) A lab-quality pregnancy test

This confirms the result in a medical setting.


2) An ultrasound (if appropriate)

An ultrasound can help determine:

  • How far along you are (gestational age)

  • Whether the pregnancy is located in the uterus

  • What options may still be available based on gestational age


This is especially important because dating a pregnancy based only on your last period or an app can be off by days or even weeks.


Contact us for a consultation and, if needed, a pregnancy confirmation appointment to learn more and explore your options. All our services are provided at no cost to you.


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Granite City

2019 Johnson Road
Granite City, IL 62040
618-451-2002

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Monday-Wednesday:
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Thursday: 9am-6pm

Fairview Heights

5016 N. Illinois St, Ste. A
Fairview Heights, IL 62208
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Mosaic Health in Granite City and Fairview Heights is a free women's health clinic in Illinois. We believe women and men have a right to get information from a resource that will not profit from the choices and pregnancy decisions they make. As a 501(c)(3) non-profit in Illinois we do not provide abortions and all our services are provided at no cost to you.

 

The information on this site is for education purposes only and should not be substituted for medical or legal advice.  Contact us to learn more.

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