Morning-After vs. Abortion Pill

A common concern that confuses many people is whether or not the morning-after pill (Plan B One-Step) is the same thing as the abortion pill (RU486). This confusion stems from mistaken beliefs about emergency contraception. It is important to realize that these two medications serve very different purposes and work completely differently from one another.

Plan D One-Step Morning After Pill
  Justin Sullivan/Getty Images

What Is the Morning-After Pill?

The morning-after pill is a hormonal contraceptive. When taken within 72 hours of unprotected sex or contraception failure, it can help to prevent pregnancy. The morning-after pill is sold over-the-counter to people of any age and consists of one pill that contains the progestin, levonorgestrel. It is sold under the following names: Plan B One-Step, Next Choice One Dose, My Way, Take Action, and AfterPill.

Although the exact way that the morning-after pill prevents pregnancy is not clear, how it works depends on where you are in your menstrual cycle. If you are already pregnant, and you take the morning-after pill, it will not harm your pregnancy and does not cause an abortion.

What Is the Abortion Pill?

The abortion pill (also referred to as Mifeprex, RU486, and mifepristone) is an early medical abortion option. It results in a termination of a pregnancy and is only used after pregnancy is established (and no more than 70 days since the first day of a woman's last menstrual period).

The abortion pill was first used safely in Europe and was approved by the U.S. Food and Drug Administration (FDA) in September 2000. The abortion pill (RU486) can be used alone but is often used with a second medication, misoprostol, to improve success rates of termination. RU486 causes the uterine lining to shed (so a fertilized egg cannot remain attached) and misoprostol causes the uterus to contract.

While RU486 is considered the abortion pill, misoprostol may be used alone safely, although it is less effective on its own. Though, when used together, medical abortion is 95% to 97% effective in terminating a pregnancy.

The availability of mifepristone in the United States has been the subject of recent legal challenges. In April 2023, a federal judge in Texas issued a ruling to suspend mifepristone's FDA approval. Shortly after, the Supreme Court ruled to allow mifepristone to remain available and returned the case to the Fifth Circuit Court of Appeals. In August 2023, that court ruled to maintain mifepristone's approval, but with restrictions on when it can be taken and where it can be made available.

The Supreme Court is expected to hear the case again, and until then, mifepristone remains available without the recent court-ordered restrictions.

Why There Is Confusion

Much of this confusion stems from beliefs about how the morning-after pill works. Plan B One-Step (as well as the other morning-after pill brands) lowers your chances of becoming pregnant by preventing or delaying ovulation and/or by interfering with sperm movement (causing it less likely that sperm will fertilize an egg).

The real misunderstanding has to do with whether or not the morning-after pill prevents a fertilized egg from implantation. Although research shows that Plan B One-Step does not interfere with implantation, the FDA labeling on the morning-after pill says that it “may inhibit implantation.”

FDA Labeling vs. Research

It seems that the research the FDA used during the approval process of the morning-after pill mainly focused on the safety and effectiveness of the main ingredient, the progestin levonorgestrel.

Because this research did not examine exactly how the morning-after pill worked, the FDA chose to include that it could affect implantation on the product’s labeling (mainly because the thinking was that because birth control pills may work by changing the lining of the uterus, the morning-after pill does, too).

That being said, the FDA now admits that the existing data and research on the morning-after pill indicates that this product does not interfere with implantation.

Debate Over Emergency Contraception

Medical experts including the FDA, The American College of Obstetricians and Gynecologists, and The National Institutes of Health agree that the establishment of a pregnancy takes several days and is not completed until a fertilized egg has implanted in the lining of the woman's uterus.

Medically, you are considered to be pregnant only after implantation has occurred.

But many individuals (including pro-life and religious organizations) continue to hold onto the mistaken belief that the morning-after pill prevents implantation of a fertilized egg. They are quick to debate its use and incorrectly label this type of contraceptive as an abortifacient (something that causes pregnancy to end prematurely and causes an abortion). This inaccurate thinking that the morning-after pill causes abortion has created a barrier to the access and use of the morning-after pill.

Women with certain religious backgrounds may not even ask about it because they have been told that it causes abortions. There are even instances where hospital emergency rooms refuse to provide the morning-after pill to women who have been raped.

A Word From Verywell

Advocates of the morning-after pill remain firm about educating people that this medication is not an agent of abortion. Medical authorities define abortion as the disruption of an implanted fertilized egg. Federal policy, as well, agrees with the medical community and defines drugs and devices that act before implantation as preventions to pregnancy rather than agents that terminate pregnancy.

The accurate way to understand the difference between these two medications:

  • The abortion pill is a method of abortion. In combination with misoprostol, it is FDA-approved to terminate a pregnancy in women up to 10 weeks pregnant (70 days or less since the first day of the last menstrual period).
  • The morning-after pill is a type of emergency contraception. It is FDA-approved to prevent pregnancy and will not harm an existing pregnancy. Medically, a woman is NOT considered to be pregnant if she has a fertilized egg that has not yet implanted in her uterus. This means that it is impossible for the morning-after pill to terminate a pregnancy since, medically, the pregnancy doesn’t exist.
8 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Cleland K, Raymond EG, Westley E, Trussell J. Emergency contraception review: evidence-based recommendations for cliniciansClin Obstet Gynecol. 2014;57(4):741–750. doi:10.1097/GRF.0000000000000056

  2. Emergency contraceptionPaediatr Child Health. 2003;8(3):181–192. doi:10.1093/pch/8.3.181

  3. American College of Obstetricians and Gynecologists’ Committee on Practice Bulletins—Gynecology, Society of Family Planning. Medication Abortion Up to 70 Days of Gestation: ACOG Practice Bulletin, Number 225Obstet Gynecol. 2020;136(4):e31-e47. doi:10.1097/AOG.0000000000004082

  4. Simmonds KE, Beal MW, Eagen-Torkko MK. Updates to the US Food and Drug Administration Regulations for Mifepristone: Implications for Clinical Practice and Access to AbortionJournal of Midwifery & Womens Health. 2017;62(3):348-352. doi:10.1111/jmwh.12636

  5. Peck R, Rella W, Tudela J, Aznar J, Mozzanega B. Does levonorgestrel emergency contraceptive have a post-fertilization effect? A review of its mechanism of actionLinacre Q. 2016;83(1):35–51. doi:10.1179/2050854915Y.0000000011

  6. Inappropriate Obstructions to Access: The FDAs Handling of Plan BAMA Journal of Ethics. 2014;16(4):295-301. doi:10.1001/virtualmentor.2014.16.4.oped1-1404

  7. Haeger KO, Lamme J, Cleland K. State of emergency contraception in the U.S., 2018Contracept Reprod Med. 2018;3:20. doi:10.1186/s40834-018-0067-8

  8. Food and Drug Association. Miferprex label.

Additional Reading

By Dawn Stacey, PhD, LMHC
Dawn Stacey, PhD, LMHC, is a published author, college professor, and mental health consultant with over 15 years of counseling experience.