title: Early serum human chorionic gonadotropin (hCG) trends after medication abortion.
abstract: OBJECTIVE
  Despite increased reliance on human chorionic gonadotropin (hCG) for early pregnancy monitoring, there is limited information about hCG trends soon after medication abortion. The purpose of this study was to determine if there is a predictable decline in serum hCG values shortly after medication abortion.
  
  
  METHODS
  This is a retrospective study of women with early intrauterine pregnancies who underwent medication abortion with mifepristone and misoprostol and had a serum hCG level on Day 1 (day of mifepristone) and a repeat value on Day 2 to 6. The percent hCG decline was calculated from baseline to repeat measure, with repeat values from the same patient accounted for through repeated measure analysis of variance.
  
  
  RESULTS
  Eighty-eight women with a mean gestational age of 5.5 weeks and median baseline hCG of 5220 IU met study criteria over a 3-year period. The mean decline (±SD) in hCG from the Day 1 baseline value was 56.9%±29.5% on Day 3, 73.5%±38.6% on Day 4, 86.1%±8.8% on Day 5, and 92.9%±3.4% on Day 6. Eighty-two women (93% of the cohort) had a complete abortion without further intervention. The least square means hCG decline among these women was 57.6% [95% confidence interval (CI): 50.3-64.9%] on Day 3, 78.9% (95% CI: 75.0-82.8%) on Day 4 and 86.2% (95% CI: 81.3-91.1%) on Day 5.
  
  
  CONCLUSIONS
  There is a rapid decline in serum hCG within the first few days after early medication abortion. Further research is needed to delineate how soon after medication abortion this decline may be specific enough to confirm abortion completion.
  
  
  CONCLUSIONS
  This study provides the largest cohort of patients followed with serial hCG values in the first few days after medication abortion. Our findings demonstrate the trend in hCG decline in this population, which may be predictable by Day 5.
authors.affiliation: Department of Obstetrics, Gynecology, and Reproductive Biology, Brigham and Women's Hospital, Boston, MA 02115, USA; Harvard Medical School, Boston, MA 02115, USA. Electronic address: kpocius@partners.org.
authors.forename: Katherine D
authors.initials: KD
authors.lastname: Pocius
authors.affiliation: Harvard Medical School, Boston, MA 02115, USA; Center for Clinical Investigation, Brigham and Women's Hospital, Boston, MA 02115, USA. Electronic address: rmaurer@partners.org.
authors.forename: Rie
authors.initials: R
authors.lastname: Maurer
authors.affiliation: Planned Parenthood League of Massachusetts, Boston, MA 02115, USA. Electronic address: jfortin@pplm.org.
authors.forename: Jennifer
authors.initials: J
authors.lastname: Fortin
authors.affiliation: Department of Obstetrics, Gynecology, and Reproductive Biology, Brigham and Women's Hospital, Boston, MA 02115, USA; Harvard Medical School, Boston, MA 02115, USA; Planned Parenthood League of Massachusetts, Boston, MA 02115, USA. Electronic address: agoldberg@pplm.org.
authors.forename: Alisa B
authors.initials: AB
authors.lastname: Goldberg
authors.affiliation: Department of Obstetrics, Gynecology, and Reproductive Biology, Brigham and Women's Hospital, Boston, MA 02115, USA; Harvard Medical School, Boston, MA 02115, USA; Planned Parenthood League of Massachusetts, Boston, MA 02115, USA. Electronic address: dbartz@partners.org.
authors.forename: Deborah
authors.initials: D
authors.lastname: Bartz
mesh_terms: D000020:Abortifacient Agents, Nonsteroidal; D000028:Abortion, Induced; D006063:Chorionic Gonadotropin / Q000097:blood*; D005260:Female; D005865:Gestational Age; D006801:Humans; D015735:Mifepristone; D016595:Misoprostol; D011247:Pregnancy; D012189:Retrospective Studies
chemical_list: D000020:Abortifacient Agents, Nonsteroidal; D006063:Chorionic Gonadotropin; D016595:Misoprostol; D015735:Mifepristone
keywords: Follow-up; Human chorionic gonadotropin; Medical abortion; Medication abortion; Mifepristone; hCG