Misoprostol Regimen for MTP at 17 Weeks Gestation
For medical termination of pregnancy at 17 weeks gestation, administer misoprostol 400 mcg vaginally every 3-6 hours (up to 5 doses maximum), which is the optimal regimen for second-trimester abortion based on efficacy and safety profile.
Recommended Dosing Protocol
- Vaginal misoprostol 400 mcg every 3-6 hours is the preferred regimen for second-trimester termination between 13-22 weeks gestation 1, 2
- The maximum recommended number of doses is 5 doses within a 24-hour period to minimize side effects while maintaining efficacy 2
- Vaginal administration is significantly more effective than oral administration, with a mean induction-to-delivery interval of 17.5 hours (vaginal) versus 33 hours (oral), and 93% delivery rate within 24 hours for vaginal route 3
Critical Considerations for Scarred Uterus
- If the patient has a previous cesarean section or uterine scar, use lower doses and longer intervals (consider 200-400 mcg every 6 hours) and never double the dose if there is no initial response 1
- Uterine rupture, though rare, is a serious complication that increases with higher doses and scarred uteri 2
Optimal Regimen with Mifepristone (When Available)
- The combination of mifepristone followed by misoprostol has the highest efficacy and shortest abortion interval for second-trimester termination 1, 2
- If mifepristone is available, administer it 24-48 hours before starting misoprostol to improve outcomes 2
Expected Efficacy and Timing
- Success rates with misoprostol alone at this gestational age range from 91.8% to over 90% 4
- Mean expulsion time is approximately 9-10 hours, with most women delivering within 24 hours 4, 3
Common Side Effects to Anticipate
- Abdominal pain/cramping occurs in approximately 80% of cases 4
- Shivering (17%), nausea/vomiting (10%), fever and chills are common 2, 4
- Gastrointestinal effects including diarrhea occur in 4-10% of cases, and are more likely with doses exceeding 800 mcg 1, 4
Management of Incomplete Abortion
- Placental retention occurs in approximately 8-9% of cases 4
- Have surgical backup available for incomplete abortion, ongoing pregnancy, or medical complications requiring intervention 5
Important Caveats
- Do not exceed 800 mcg total dose per administration cycle as higher doses significantly increase side effects, particularly diarrhea, without improving efficacy 1
- For gestational ages beyond 22 weeks, reduce both dose and frequency of administration due to increased uterine sensitivity 2
- Counsel patients about teratogenic risks if abortion fails, as misoprostol exposure is associated with congenital anomalies 1