Up to how many weeks of gestation can medication abortion be safely performed?

Medication Abortion Gestational Age Limits

Medication abortion can be safely performed up to 70 days (10 weeks) of gestation using the FDA-approved mifepristone-misoprostol regimen, though evidence supports its use up to 77 days in clinical practice. 1, 2

Standard Gestational Age Limits

FDA-Approved Protocol

• The FDA-approved regimen of mifepristone and misoprostol is indicated for medication abortion up to 70 days (10 weeks) of gestation. 1
• This represents the official regulatory limit for the standard medication abortion protocol in the United States. 1

Evidence-Based Clinical Practice

• Clinical evidence supports medication abortion up to 77 days (11 weeks) of gestation using mifepristone 200 mg orally followed by misoprostol 800 mcg buccally or vaginally. 2
• The same regimen is also safe and effective for early pregnancy loss management up to 84 days (12 weeks) of gestation. 2

Beyond 10-11 Weeks

Second Trimester Medication Abortion

• Between 14 0/7 and 27 6/7 weeks of gestation, medication abortion remains an option but requires different dosing protocols and clinical management. 3, 4
• Mifepristone 200 mg followed by misoprostol is more effective than misoprostol alone in this gestational age range. 3, 4, 5
• At 12 weeks and above, a 24-hour interval between mifepristone and misoprostol administration reduces ongoing pregnancy rates compared to simultaneous dosing. 5

Critical Safety Considerations

Uterine Rupture Risk

• Misoprostol should not be used after the eighth week of pregnancy for labor induction due to risk of uterine rupture, according to FDA labeling. 6
• However, this warning applies to labor induction, not medication abortion protocols, which use different dosing regimens. 6
• In medication abortion between 14-27 weeks with two or more prior cesarean sections, uterine rupture risk is increased but remains low overall. 3, 4

Gestational Age Determination

• Ultrasonography or reliable menstrual history must be used to confirm gestational age before proceeding. 2
• Ultrasonography is mandatory when dating cannot be confirmed clinically or when ectopic pregnancy risk factors are present. 2

Common Pitfalls to Avoid

• Do not confuse FDA approval limits (70 days) with evidence-based practice limits (77 days) - both are acceptable, but clinical evidence extends slightly beyond FDA labeling. 1, 2
• Do not apply the "eighth week" uterine rupture warning from labor induction protocols to medication abortion - these are different clinical contexts with different dosing regimens. 6
• Do not proceed without confirming gestational age - misdiagnosis can lead to treatment failure or missed ectopic pregnancy. 2
• Do not forget Rh testing and RhIg administration - even at early gestational ages (<12 weeks), fetal RBCs display Rh antigens from 6 weeks onward, making sensitization possible. 7