| NOTICE: If you’ve only taken the first pill, mifepristone, and are having second thoughts about your decision, contact CompassCare immediately for an emergency progesterone therapy consultation. |
A failed medication abortion is what happens when the abortion pill (mifepristone and misoprostol) does not completely end a pregnancy.
If a medication abortion fails there are at least 3 potential outcomes:
- A healthy pregnancy may continue.
- The baby may die, and fetal tissue remains in the uterus (incomplete abortion). This is an emergency.
- The embryo may not be located in the uterus but rather in the fallopian tubes (ectopic). This is also an emergency.
A follow-up ultrasound is the most reliable way to confirm the outcome and is essential to ensure appropriate next steps are taken.
What Is the Abortion Pill?
The abortion pill is actually a two-part pharmaceutical regimen, also referred to as a chemical or medication abortion. Distinctly different than the “morning-after pill” (or its brand name, “Plan B”), which is an emergency contraceptive for use immediately following unprotected sex, the “abortion pill” refers to a series of medications—mifepristone and misoprostol—taken to induce an abortion in a woman already confirmed to be pregnant. The abortion drug regimen is recommended only up to 10 weeks gestation. How Does the Abortion Pill Work?
| Step | Medication | Dose/Timing | Mechanism/Action | Result |
| 1 | Mifepristone | Single pill administered orally before 10 weeks’ gestation. | Blocks progesterone, the hormone necessary to sustain fetal gestation, causing the baby to die. | Without sufficient progesterone support, fetal growth ceases, and if the fetus is at an early enough stage of development, it will not survive. As pregnancy advances, the likelihood that mifepristone alone will result in fetal death decreases. |
| 2 | Misoprostol | 4 pills administered at home 24-48 hours later. | Softens and dilates the cervix while stimulating contractions of the uterus, which leads to the expulsion of uterine contents. | Depending on how far along in the pregnancy, if the baby remains alive after mifepristone administration, the expulsion process caused by misoprostol often is the cause of the death of the baby. |
Read more about how the abortion pill works and the risks associated with a medication abortion.
Frequently Asked Questions
Can the abortion pill fail?
Yes, there are three ways a medication abortion can fail.
- The pregnancy is still ongoing (the baby remains alive).
- The pregnancy has stopped developing (the baby dies), but the fetal tissue remains in the uterus; also referred to as an incomplete abortion.
- The pregnancy is ectopic. “Mifepristone and misoprostol do not terminate ectopic pregnancy.”1
How often does the abortion pill fail?
The risk of failure increases with gestational age. According to a systematic review cited by ACOG, the ongoing pregnancy rate after the standard mifepristone-misoprostol regimen was 1-2% through 63 days’ gestation2; however, studies performed beyond 63 days reported that number to be upward of 8. Unsuccessful expulsion requiring surgical intervention was higher for those who started the regimen after 10 weeks.
| Days Gestation | Pregnancy Continued | Surgical Intervention Required |
| 64-70 | 3.6% | 7.7% |
| 71-77 | 8.7% | 13.3% |
Mifepristone becomes less effective after 10 weeks, as the fetus begins producing its own progesterone
Will I be able to tell if the abortion pill failed?
No, you may not know if a medication abortion has failed. Even if the abortion pill does not end the pregnancy, many women still experience symptoms that feel very much like a menstrual period or miscarriage, such as:
- Cramping (sometimes intense)
- Bleeding that may be as heavy as or heavier than a period
- Passage of blood clots
- Nausea
- Diarrhea
- Chills or low-grade fever
- Fatigue
“Even if a pregnancy is ectopic, a woman can experience some bleeding after taking mifepristone and misoprostol because the decidua [uterine lining] may respond to the medications.”1
It is recommended that women who undergo a medication abortion follow up with their primary care physician (PCP) or gynecologist (OB/GYN) at least two weeks after completing the two-step regimen.
What happens if the pregnancy continues after taking abortion pills?
An ultrasound by a qualified practitioner provides the clearest assessment of whether your medication abortion has failed.
If your doctor determines that your baby is still alive, you may opt to:
- Continue the pregnancy and follow up with an OB/GYN, or
- Complete the abortion with additional medication or a procedural abortion.
If your baby is deceased but has not been expelled, your doctor may recommend:
- Attempting to complete the abortion with additional misoprostol, or
- Having the remains surgically removed.
Signs the abortion pill may have failed:
- Ongoing pregnancy symptoms
- Persistent positive pregnancy tests
- Lack of expected bleeding
Can the abortion pill treat an ectopic pregnancy?
No, the abortion pill cannot resolve an ectopic pregnancy. Because the growing fetus is located in the fallopian tube and not the uterus, uterine contractions will not expel the pregnancy. Ectopic pregnancies can be life-threatening and women with a confirmed or suspected ectopic pregnancy should not use mifepristone or misoprostol. An ultrasound should be performed before an abortion procedure to rule out ectopic pregnancy, confirm viability, and accurately determine gestational age.
Schedule a free ultrasound now.
If a medication abortion fails, is the fetus affected?
The health of your baby depends on the stage at which the medication abortion fails. There is no evidence that mifepristone alone causes birth defects, so if the pregnancy is sustained after the use of mifepristone only, the pregnancy should continue normally. However, when misoprostol is used during the first trimester, congenital anomalies such as limb defects1 can occur.
How safe is the abortion pill?
The FDA is currently reviewing the safety of the drug (Mifepristone) due to recent data revealing that up to 1 in 10 women who begin the abortion pill process end up in the emergency room with complications including sepsis, hemorrhage, and other related complications.
What if I’ve taken the abortion pill but then change my mind?
It may be possible to continue a healthy pregnancy. If you’ve taken only the first pill (mifepristone) and have NOT taken the misoprostol, contact us immediately. Pregnancy-sustaining progesterone therapy can be administered with the goal of supporting the pregnancy and giving it the best chance of continuing.
Learn more about Abortion Pill Reversal.
Medically Reviewed by:
Shirley Defendis, RN, BSN
1 Clinical Practice Handbook for Safe Abortion: NCBI Bookshelf. 2.4. Medical Abortion Clinical considerations. Geneva: World Health Organization (2014). PDF
2 ACOG Practice Bulletin No. 225: Medication Abortion Up to 70 Days of Gestation (2020). American College of Obstetricians and Gynecologists’ Committee on Practice Bulletins—Gynecology, Society of Family Planning. Creinin M., Grossman D. PDF
3 Contraception Volume 101, Issue 5, May 2020: A non-inferiority study of outpatient mifepristone-misoprostol medical abortion at 64–70 days and 71–77 days of gestation (2020). I. Dzuba, E. Chong, C. Hannum, E. S. Lichtenberg, E. Hernández, N. Thi Nhu Ngoc, A. Patel, G. Rzayeva, P. Sanhueza Smith, G. Tsertsvadze, B. WinIikoff. PDF
4 MIFEPREX™ (mifepristone) Tablets, 200 mg For Oral Administration Only. Retrieved from accessdata.fda.gov 06-11-26. PDF.