Introduction

Medical abortion involves the use of pharmaceutical drugs to terminate an early pregnancy. It is a safe and effective alternative to surgical abortion, particularly in the early weeks of pregnancy. Various medications and regimens are approved for medical abortion, with mifepristone and misoprostol being the most commonly used combination. This lecture explores the approved medications, their mechanisms of action, and the different regimens for administering medical abortion.

1. Approved Medications for Medical Abortion

A. Mifepristone

• Mechanism of Action:

  • Mifepristone is an anti-progestogen that works by blocking the hormone progesterone, which is essential for maintaining pregnancy. Without progesterone, the lining of the uterus breaks down, and the pregnancy cannot continue.
  • It is typically used as the first step in a two-drug regimen for medical abortion.

• Administration:

  • Mifepristone is taken orally, usually as a single dose of 200 mg.
  • The medication is usually administered in a healthcare setting, although it may also be prescribed for home use in certain jurisdictions, depending on local regulations.

B. Misoprostol

• Mechanism of Action:

  • Misoprostol is a prostaglandin analog that causes the uterus to contract, leading to the expulsion of the pregnancy tissue. It is used in combination with mifepristone to complete the abortion process.
  • Misoprostol can also be used alone for abortion in settings where mifepristone is not available, though this regimen is less effective.

• Administration:

  • Misoprostol can be administered orally, buccally (dissolved in the mouth between the cheek and gum), sublingually (under the tongue), or vaginally. The route of administration may vary depending on the clinical guidelines and patient preference.
  • The typical dosage is 800 mcg (four 200 mcg tablets), taken 24 to 48 hours after mifepristone.

C. Methotrexate (Less Commonly Used)

• Mechanism of Action:

  • Methotrexate is an anti-metabolite that inhibits the growth of rapidly dividing cells, such as those in the early pregnancy tissue. It is sometimes used in combination with misoprostol for medical abortion, particularly in settings where mifepristone is not available.
  • Methotrexate is less commonly used for abortion today due to the availability of mifepristone, which is more effective and has a faster onset of action.

• Administration:

  • Methotrexate is administered either orally or by injection, followed by misoprostol to induce uterine contractions.
  • The abortion process with methotrexate can take longer (several days to weeks) compared to the mifepristone-misoprostol regimen.

2. Approved Regimens for Medical Abortion

A. Mifepristone and Misoprostol Regimen

• Standard Protocol (Up to 10 Weeks Gestation):

  • Step 1: Mifepristone (200 mg)
    • The patient takes a single dose of 200 mg mifepristone orally. This medication blocks progesterone, leading to the breakdown of the uterine lining and detachment of the pregnancy.
  • Step 2: Misoprostol (800 mcg)
    • 24 to 48 hours after taking mifepristone, the patient takes 800 mcg of misoprostol either orally, buccally, sublingually, or vaginally. Misoprostol causes the uterus to contract, expelling the pregnancy tissue.
  • Outcome:
    • The abortion process typically begins within a few hours after taking misoprostol, with bleeding and cramping as the main symptoms. The process may take a few hours to complete, and bleeding can continue for several days to weeks.

• Alternative Regimen (For Gestations Between 10 and 12 Weeks):

  • The mifepristone dose remains the same (200 mg), but the misoprostol dose may be increased or repeated to ensure complete abortion. Some protocols recommend a second dose of 800 mcg misoprostol 3-4 hours after the first dose, or additional doses if necessary.
  • This regimen is still effective but may require closer medical supervision and follow-up to ensure the abortion is complete.

B. Misoprostol-Only Regimen (Where Mifepristone is Not Available)

• Protocol:
  • Step 1: Misoprostol (800 mcg)
    • The patient takes an initial dose of 800 mcg of misoprostol, administered either buccally, sublingually, or vaginally.
  • Step 2: Additional Doses if Needed
    • If the abortion is not complete after the first dose, additional doses of 800 mcg misoprostol may be administered every 3-12 hours, up to a maximum of three doses.
  • Outcome:
    • This regimen is less effective than the mifepristone-misoprostol combination, with success rates ranging from 75% to 90%, depending on gestational age and the number of doses used.

C. Methotrexate and Misoprostol Regimen (Less Commonly Used)

• Protocol:
  • Step 1: Methotrexate
    • The patient receives a dose of methotrexate, either orally (50 mg/m²) or by injection (50 mg/m² intramuscularly).
  • Step 2: Misoprostol (800 mcg)
    • After 3-7 days, the patient takes 800 mcg of misoprostol to induce uterine contractions.
  • Outcome:
    • The abortion process with methotrexate and misoprostol can take longer to complete, often requiring a follow-up visit to ensure the abortion is successful. This method is less commonly used due to the longer time frame and the availability of more effective regimens.

3. Managing Side Effects and Complications

A. Common Side Effects

• Bleeding and Cramping:

  • Heavy bleeding and cramping are expected after taking misoprostol as the uterus expels the pregnancy tissue. This can last for several hours, with lighter bleeding potentially continuing for up to two weeks.
  • Pain relief options, such as NSAIDs (e.g., ibuprofen), can be used to manage cramping.

• Nausea, Vomiting, and Diarrhea:

  • These gastrointestinal symptoms can occur after taking misoprostol. Anti-nausea medications may be prescribed to help manage these side effects.

• Fever and Chills:

  • Some patients may experience mild fever, chills, or flu-like symptoms after taking misoprostol. These symptoms usually resolve on their own within a few hours.

B. Complications

• Incomplete Abortion:

  • If the abortion is incomplete, meaning some pregnancy tissue remains in the uterus, a follow-up procedure, such as surgical aspiration, may be necessary to remove the remaining tissue.

• Infection:

  • Although rare, infection is a potential complication of medical abortion. Signs of infection include persistent fever, foul-smelling vaginal discharge, or severe abdominal pain. Immediate medical attention is required if infection is suspected.

• Heavy Bleeding:

  • While bleeding is expected, excessively heavy bleeding (soaking more than two sanitary pads per hour for two consecutive hours) may indicate a complication and requires prompt medical evaluation.

C. Follow-Up Care

• Confirming Completion:

  • A follow-up visit is typically scheduled 1-2 weeks after the abortion to confirm that the procedure was successful and that no pregnancy tissue remains. This can be done through an ultrasound or a blood test to measure hCG levels.
  • Patients should be informed of the signs of complications and instructed to seek medical care if they experience severe pain, heavy bleeding, or signs of infection.

• Emotional Support:

  • Counseling and emotional support should be offered to patients after the procedure. Some patients may experience feelings of sadness, relief, or other emotions, and access to support services can be beneficial.

4. Considerations for Choosing a Medical Abortion Protocol

A. Gestational Age

• Early Pregnancy (Up to 10 Weeks):

  • The standard mifepristone-misoprostol regimen is most effective during this period, with a high success rate and minimal complications.

• Later in the First Trimester (10 to 12 Weeks):

  • While still effective, additional doses of misoprostol may be necessary to ensure the abortion is complete. Surgical options may also be discussed as an alternative.

B. Patient Preference

• Desire for Privacy and Control:

  • Medical abortion allows the patient to manage the process at home, which can be appealing for those who value privacy and control over their healthcare.

• Tolerance for Side Effects:

  • Patients should be informed about the potential for cramping, bleeding, and other side effects. Those who prefer a less physically intense experience may opt for surgical abortion instead.

C. Accessibility of Medications

• Availability of Mifepristone:

  • In some regions, access to mifepristone may be limited, necessitating the use of misoprostol-only regimens or other alternatives like methotrexate and misoprostol.

• Healthcare Setting:

  • The choice of protocol may also depend on whether the patient is able to visit a healthcare facility or needs to manage the process at home due to geographical or logistical constraints.

Real-World Case Studies

Case Study 1: Medical Abortion at 8 Weeks Gestation

Scenario:
A 28-year-old woman, 8 weeks pregnant, seeks a medical abortion. She prefers a non-invasive method and wishes to complete the process at home.

Discussion Points:

• What is the most appropriate medical abortion regimen for her?
• How should she be counseled on what to expect during the process?
• What follow-up care is necessary to ensure the abortion is complete?

Resolution:
The standard mifepristone-misoprostol regimen is recommended. She should be informed about the timing, expected side effects (bleeding, cramping), and signs of complications. A follow-up appointment should be scheduled 1-2 weeks after the abortion to confirm completion.

Case Study 2: Misoprostol-Only Abortion Protocol

Scenario:
A 32-year-old woman in a region where mifepristone is not available seeks an abortion at 9 weeks gestation.

Discussion Points:

• What is the appropriate misoprostol-only regimen for this patient?
• How should the patient be monitored for effectiveness and potential complications?
• What should be done if the abortion is incomplete?

Resolution:
The patient should take 800 mcg of misoprostol buccally or vaginally. If the abortion is incomplete, additional doses may be administered. She should be monitored for heavy bleeding or infection and advised to seek immediate care if complications arise. Follow-up is essential to confirm the abortion’s success.

End of Lecture Quizzes

1. What is the primary mechanism of action for mifepristone in medical abortion?

   • A) Inducing uterine contractions
   • B) Blocking progesterone
   • C) Inhibiting cell division
   • D) Thinning the uterine lining
     Answer: B
     Rationale: Mifepristone works by blocking progesterone, a hormone necessary for maintaining pregnancy.

2. Which of the following is a common side effect after taking misoprostol during a medical abortion?

   • A) Severe headache
   • B) Constipation
   • C) Cramping and bleeding
   • D) High blood pressure
     Answer: C
     Rationale: Cramping and bleeding are common side effects as the uterus expels the pregnancy tissue after taking misoprostol.

3. What is a key difference between the mifepristone-misoprostol regimen and the misoprostol-only regimen?

   • A) The misoprostol-only regimen is more effective
   • B) The mifepristone-misoprostol regimen has a shorter duration
   • C) The misoprostol-only regimen is less likely to cause side effects
   • D) The mifepristone-misoprostol regimen requires hospitalization
     Answer: B
     Rationale: The mifepristone-misoprostol regimen typically has a shorter duration and higher effectiveness compared to the misoprostol-only regimen.

4. Which method is least commonly used today for medical abortion?

   • A) Mifepristone and misoprostol
   • B) Methotrexate and misoprostol
   • C) Misoprostol-only
   • D) Dilation and curettage
     Answer: B
     Rationale: Methotrexate and misoprostol is less commonly used today due to the availability of more effective and faster-acting regimens like mifepristone and misoprostol.

Curated List of Online Resources for Further Information

1. Planned Parenthood – Medical Abortion:
   Detailed information on medical abortion, including medications, regimens, and what to expect.
   Planned Parenthood

2. World Health Organization (WHO) – Safe Abortion:
   WHO guidelines on the safe use of medical abortion, including approved medications and protocols.
   WHO – Safe Abortion

3. American College of Obstetricians and Gynecologists (ACOG) – Medication Abortion:
   ACOG recommendations and guidelines for the use of medications in abortion care.
   ACOG – Medication Abortion

4. Guttmacher Institute – Medical Abortion:
   Research and data on the use and effectiveness of medical abortion protocols worldwide.
   Guttmacher Institute

5. National Abortion Federation (NAF) – Clinical Policy Guidelines:
   NAF’s clinical guidelines on medical abortion, including protocols and patient management.
   NAF – Clinical Guidelines

Summary

Medical abortion is a safe and effective method for terminating early pregnancies, typically up to 10 weeks gestation. The most commonly used regimen involves the combination of mifepristone and misoprostol, which is highly effective and widely approved. Misoprostol can also be used alone in settings where mifepristone is not available, although it is less effective. Understanding the protocols, potential side effects, and the importance of follow-up care is essential for providing comprehensive and patient-centered abortion care.

These lecture notes provide a comprehensive overview of medical abortion protocols, equipping students with the knowledge needed to understand the medications, regimens, and clinical considerations involved in medical abortion.