If your period is late and you’re worried about an unplanned pregnancy, you may have heard about “period pills” or “missed period pills.” These terms have gained attention recently, but what exactly are they, and what should you know before considering them?
At Pregnancy Resource Center, we believe in empowering you with complete, accurate information so you can make the healthiest decision for your unique situation. Keep reading to learn more about missed period pills.
What Are Missed Period Pills?
Missed period pills, also called period pills, refer to medications that induce bleeding if your period is late.
However, if you are pregnant, these medications will end the pregnancy. This is what medical professionals classify as a medication abortion.
How Do Missed Period Pills Work?
Period pills often consist of misoprostol, but can be used in combination with mifepristone.
Here’s how it works:
- Mifepristone may be taken if a woman thinks she is pregnant. This drug blocks the hormone progesterone, which is necessary to sustain the pregnancy. Without progesterone, the pregnancy cannot continue, and the embryo stops growing.
- Misoprostol triggers uterine contractions to induce bleeding and expel the pregnancy (if the woman is pregnant).
Risks and Side Effects
It’s crucial to understand both common side effects and potential serious complications before taking period pills.
Common Side Effects
Most women who take period pills experience[1]:
- Heavy bleeding and cramping that can be more intense than a typical period
- Nausea and vomiting
- Diarrhea and digestive pain
- Fever and chills
- Headache and dizziness
Serious Complications
While rare, serious complications can occur. Seek immediate medical attention if you experience[1][2]:
- Heavy bleeding—soaking through two or more pads per hour for two consecutive hours
- Fever above 100.4°F, especially if it persists beyond 24 hours
- Blood clots larger than a lemon
- Signs of infection, including foul-smelling vaginal discharge
- Incomplete abortion
Why Pregnancy Tests and Ultrasounds Matter
Period pills are often prescribed to women before they have taken a pregnancy test or received an ultrasound. However, you should never skip these steps. They are safeguards designed to protect your health and help you make a fully informed decision.
Here’s why you should take a pregnancy test and receive an ultrasound before taking period pills:
Confirming a Viable Pregnancy
You should first take a pregnancy test to confirm that you are actually pregnant. However, a positive pregnancy test does not mean you have a viable, ongoing pregnancy. An ultrasound is the fastest, most accurate way to confirm whether there is a heartbeat and a developing pregnancy.
Research shows that 10-20% of known pregnancies end in miscarriage.[3] If your pregnancy is not viable, you don’t need to take period pills. Your body will naturally complete the miscarriage process.
Determining Gestational Age
An ultrasound is the most accurate way to determine how far along you are (gestational age). This is important to know, because these pills are only FDA-approved for up to 10 weeks (70 days) of pregnancy.[4]
Ruling Out Ectopic Pregnancy
One of the most critical reasons for an ultrasound is to rule out an ectopic pregnancy. This is when a fertilized egg implants outside the uterus, usually in a fallopian tube. Only an ultrasound can confirm that your pregnancy is located in the uterus, not in your fallopian tube or elsewhere.
If not diagnosed in time, an ectopic pregnancy can rupture, causing life-threatening internal bleeding. This is a medical emergency that requires immediate treatment.
Here’s the crucial point: Period pills do not work on ectopic pregnancies.[4] If you take period pills, you will experience all the side effects, but it will not end the ectopic pregnancy.
Understanding Your Complete Health Picture
Beyond confirming pregnancy details, you should also speak to a medical professional to evaluate your health to identify factors that might affect your safety.
You should not take period pills if you have[4]:
- You’re more than ten weeks pregnant (from the first day of your last menstrual period)
- You have an IUD (Intrauterine Device) currently in place
- You have a clotting disorder or certain other medical conditions
- You have an ectopic pregnancy or suspect you might have one
- You take long-term corticosteroid therapy or have adrenal gland problems
- You’re allergic to any of the ingredients in the medication
We’re Here to Help
You don’t have to navigate this decision alone. Pregnancy Resource Center is here to provide the information, resources, and support you need to make the best decision for your health and future.
We offer free, confidential services including:
- Pregnancy testing
- Limited ultrasounds
- Pregnancy options education
- Referrals to community resources
Give us a call at (740) 592-4700 or schedule your appointment online today.
Please be aware that Pregnancy Resource Center does not provide or refer for abortion services.
The information provided in this article is for educational purposes and should not replace medical advice from a qualified healthcare professional. If you’re experiencing a medical emergency, please call 911 or go to your nearest emergency room immediately.
Sources
- U.S. National Library of Medicine. (2024, November 15). Mifepristone (Mifeprex). MedlinePlus. https://medlineplus.gov/druginfo/meds/a600042.html
- U.S. National Library of Medicine. (2025, May 22). Ending pregnancy with medicines. MedlinePlus. https://medlineplus.gov/ency/patientinstructions/000835.htm
- Mayo Clinic. (2023, September 8). Miscarriage – Symptoms & Causes. https://www.mayoclinic.org/diseases-conditions/pregnancy-loss-miscarriage/symptoms-causes/syc-20354298
- FDA. (2025, February 11). Questions and Answers on Mifeprex. U.S. Food and Drug Administration. https://www.fda.gov/drugs/postmarket-drug-safety-information-patients-and-providers/questions-and-answers-mifeprex