Risk factors for unsuccessful medical abortion with mifepristone and misoprostol

Acta Obstet Gynecol Scand. 2007;86(4):462-6. doi: 10.1080/00016340701203632.

Abstract

Background: The aim of this study was to determine the effectiveness of medical abortions with mifepristone and misoprostol following the approval of medical abortion in Israel.

Methods: A retrospective review of 377 consecutive medical records at an ambulatory care unit of a university medical centre was performed, screening all women undergoing medical abortion with mifepristone and misoprostol. Transvaginal ultrasonographic study and serum beta hCG measurement were performed 14-20 days after the procedure. The clinical outcome was defined as complete expulsion of intrauterine contents with (failed group) or without (successful group) surgical intervention.

Results: Surgical intervention was performed in 7.4% of patients. Residual products of conception were confirmed in 89%. Older age, previous spontaneous abortions, multigravidity, and earlier follow-up visit were independently associated with unsuccessful medical abortion. Significant differences were found in mean serum beta hCG and mean endometrial thickness in the successful versus failed procedure groups.

Conclusions: Medical termination of pregnancy with mifepristone and misoprostol is >90% effective. High risk group for failure of the procedure can be characterised. An algorithm of follow up using follow-up visit date, serum beta hCG and sonographic endometrial stripe is suggested to define high risk patients for failed medical abortion.

MeSH terms

  • Abortifacient Agents, Nonsteroidal / adverse effects*
  • Abortifacient Agents, Nonsteroidal / therapeutic use
  • Abortifacient Agents, Steroidal / adverse effects*
  • Abortifacient Agents, Steroidal / therapeutic use
  • Abortion, Induced* / methods
  • Abortion, Spontaneous
  • Adolescent
  • Adult
  • Chorionic Gonadotropin, beta Subunit, Human / blood
  • Drug Therapy, Combination
  • Female
  • Humans
  • Logistic Models
  • Middle Aged
  • Mifepristone / adverse effects*
  • Mifepristone / therapeutic use
  • Misoprostol / adverse effects*
  • Misoprostol / therapeutic use
  • Parity
  • Pregnancy
  • Retrospective Studies
  • Risk Factors
  • Treatment Failure
  • Treatment Outcome
  • Ultrasonography
  • Uterus / diagnostic imaging

Substances

  • Abortifacient Agents, Nonsteroidal
  • Abortifacient Agents, Steroidal
  • Chorionic Gonadotropin, beta Subunit, Human
  • Misoprostol
  • Mifepristone