What is Mifepristone (the abortion pill)
Mifepristone (also known as RU-486) is a medication primarily used to terminate early pregnancies. It belongs to a class of drugs called progesterone receptor antagonists. Mifepristone works by blocking the action of progesterone, a hormone that is essential for the continuation of a pregnancy. Without progesterone, the lining of the uterus breaks down, preventing the embryo from developing further.
Progesterone is a hormone that plays a crucial role in the female reproductive system, as well as in the maintenance of pregnancy. It is mainly produced in the ovaries after ovulation, but smaller amounts are also produced by the adrenal glands and, during pregnancy, by the placenta.
Progesterone has several important functions in the body, including:
- Regulating the menstrual cycle: Progesterone works together with estrogen to prepare the uterus for a possible pregnancy. After ovulation, progesterone levels rise, thickening the uterine lining to provide a suitable environment for a fertilized egg to implant.
- Supporting pregnancy: If fertilization occurs, progesterone levels continue to rise, maintaining the uterine lining and preventing further ovulation. This hormone also helps in the development of the placenta and inhibits uterine contractions, which could potentially dislodge the implanted embryo.
- Breast development: Progesterone, along with estrogen, is responsible for the growth and development of breast tissue, particularly during pregnancy in preparation for lactation.
- Other functions: Progesterone also plays a role in mood regulation, bone health, and the maintenance of normal blood clotting.
Mifepristone is typically used in combination with another medication called misoprostol, which causes the uterus to contract and expel the embryo and uterine lining. This combination is used for medical abortion within the first 10 weeks of pregnancy. The effectiveness of this regimen is around 95-98%.
Misoprostol is a synthetic prostaglandin E1 (PGE1) analogue that has various medical applications, most notably in the context of pregnancy termination, labor induction, and the prevention and treatment of gastric ulcers. It was originally developed for the treatment of gastric ulcers, particularly in patients taking nonsteroidal anti-inflammatory drugs (NSAIDs), which can cause gastric irritation.
Here is a list detailing the effectiveness of the abortion pill:
- For those up to 8 weeks pregnant, it is effective in 94-98 cases per 100.
- For those between 8 and 9 weeks pregnant, it is effective in 94-96 cases per 100.
- For those between 9 and 10 weeks pregnant, it is effective in 91-93 cases per 100. With an additional dose of medication, the efficacy increases to 99 per 100.
- For those between 10 and 11 weeks pregnant, it is effective in 87 cases per 100. With an additional dose of medication, the efficacy increases to 98 per 100.
In addition to its use in early pregnancy termination, mifepristone has also been used to treat certain cases of Cushing's syndrome and is being investigated for other potential applications, such as the treatment of some types of cancer and psychiatric disorders.
History of Mifepristone
Mifepristone has an interesting history, marked by a series of milestones that led to its development and approval as a medication for early pregnancy termination. Below is a list of key events in the history of Mifepristone:
- 1980: Mifepristone (RU-486) was first synthesized by Dr. Etienne-Emile Baulieu and his team at Roussel Uclaf, a French pharmaceutical company. The compound was initially developed as a progesterone antagonist.
- 1982: The first clinical trials of Mifepristone for pregnancy termination began in Geneva, Switzerland, and showed promising results.
- 1988: Mifepristone was approved for use in France as a medical abortion pill, sparking a significant debate due to its controversial nature.
- 1991: Amid growing international pressure and protests, Roussel Uclaf announced that they would no longer distribute Mifepristone in France. However, the French government intervened and ordered the company to continue distributing the drug, citing its importance for women's reproductive rights.
- 1994: The Population Council, a nonprofit organization, obtained the rights to Mifepristone from Roussel Uclaf, allowing for further research and development in the United States.
- 2000: The U.S. Food and Drug Administration (FDA) approved Mifepristone, also known as Mifeprex, for use in the United States for the termination of early pregnancies.
- 2016: The FDA updated its guidelines for Mifepristone usage, allowing for a broader range of healthcare providers to prescribe the drug and extending its approved use up to 10 weeks into pregnancy.
Since its development, Mifepristone has played a significant role in providing an alternative to surgical abortion and has been used by millions of women worldwide. Its history is marked by both scientific advancements and social and political controversies.
What are the side effects of Mifepristone
Mifepristone, when used for medical abortion or other purposes, can cause a range of side effects. Some side effects are expected and considered normal, while others may be more severe and warrant medical attention. Common side effects of mifepristone include:
- Bleeding: Heavy bleeding or spotting is expected after taking mifepristone, as it causes the breakdown of the uterine lining.
- Cramping: Abdominal cramps or pain can occur as the uterus contracts to expel its contents.
- Nausea and vomiting: Some people may experience nausea or vomiting after taking mifepristone.
- Diarrhea: Mifepristone can cause gastrointestinal side effects, including diarrhea, in some individuals.
- Headache: Headaches are a common side effect of mifepristone.
- Dizziness: Some people may experience dizziness or lightheadedness after taking the medication.
- Fatigue: Mifepristone can cause tiredness or weakness in some individuals.
- Fever and chills: A low-grade fever or chills may occur after taking mifepristone, but a high fever can be a sign of infection and should be reported to a healthcare professional.
In rare cases, more serious side effects can occur, such as severe hemorrhage, infection, or an incomplete abortion.
Who should not take Mifepristone
Mifepristone is not suitable for everyone, and there are certain conditions or situations in which its use may be contraindicated. Some individuals who should not take mifepristone include:
- Those with an ectopic pregnancy: Mifepristone is not effective in treating ectopic pregnancies (when the fertilized egg implants outside the uterus, usually in a fallopian tube), which can be life-threatening if not treated properly.
- Those with certain medical conditions: People with chronic adrenal failure, uncontrolled bleeding disorders, inherited porphyria, or severe liver, kidney, or heart problems should avoid taking mifepristone.
- Those with an intrauterine device (IUD) in place: If an IUD is in place, it should be removed before using mifepristone.
- Those with known allergies: People who are allergic to mifepristone or any of its components should not take the medication.
- Those on certain medications: Some medications, such as anticoagulants, corticosteroids, or other drugs that may interact with mifepristone, could increase the risk of complications. Consult your healthcare provider for advice.
- Pregnancies beyond the approved gestational age: Mifepristone is approved for use in early pregnancy termination up to a specific gestational age (usually up to 10 weeks). It may be less effective and carry higher risks for pregnancies beyond that limit.
- Those who cannot access emergency medical care: People who live far from medical facilities or cannot access emergency care within a reasonable time should not take mifepristone, as complications may require urgent medical attention.
This list is not exhaustive, and individual circumstances may vary. Always consult a healthcare professional to determine if mifepristone is appropriate for you. They will assess your medical history, current health status, and any potential contraindications or risks before prescribing the medication.
Are there other medications similar to Mifepristone
While mifepristone is the most well-known medication for medical abortion, there is another drug called ulipristal acetate that is also a progesterone receptor antagonist, similar in action to mifepristone.
Ulipristal acetate is primarily used as an emergency contraceptive under the brand name ella (or EllaOne in some countries). It can be taken up to 120 hours (5 days) after unprotected intercourse to prevent pregnancy. Ulipristal acetate works by inhibiting or delaying ovulation, making it harder for a fertilized egg to implant in the uterus.
Although ulipristal acetate has been studied for use in early pregnancy termination, it is not currently approved for this purpose in most countries. Research has shown that it may be effective when combined with a prostaglandin such as misoprostol, similarly to the mifepristone-misoprostol regimen. However, mifepristone remains the primary medication used for early medical abortion in most cases.