title: Predictive Value of Second-Trimester Biomarkers and Maternal Features for Adverse Pregnancy Outcomes.
abstract: OBJECTIVE
  To establish the predictive probability for placenta-associated morbidities using second-trimester α-fetoprotein (AFP), human chorionic gonadotropin (HCG), and maternal features.
  
  
  METHODS
  A retrospective database of all singleton deliveries with available second-trimester HCG and AFP results from 2005 to 2012 was built and divided into 0, 1, or 2 elevated markers (defined as ≥2 multiples of the median [MoM]). For each group, we analyzed the risk for adverse obstetric outcome - comprising preeclampsia, placental abruption, and birth weight below the 10th percentile - and the time of delivery in those pregnancies. Additionally, prediction models for adverse obstetric outcome, using logistic regression incorporating AFP, HCG, and other maternal characteristics, were calculated.
  
  
  RESULTS
  Among 22,124 women who delivered, 16,197 (73%) had AFP and HCG results. Compared with the group with normal markers, the adverse obstetric outcome rate was mildly increased with elevated HCG or AFP, but it was markedly increased when both markers were elevated (13 vs. 31%, OR 2.9, 95% CI 2.0-4.3). Delivery of newborns with adverse obstetric outcome was earlier with each additional elevated marker. The accuracy of predicting adverse obstetric outcome was improved by using prediction models for women with HCG or AFP ≥1.2 MoM that incorporated maternal age, BMI, parity, and chronic hypertension (C-statistic 61-75%).
  
  
  CONCLUSIONS
  HCG and AFP combined with other maternal characteristics are useful tools for predicting the risk for adverse obstetric outcome.
authors.affiliation: Department of Obstetrics and Gynecology, Emek Medical Center, Afula, Israel.
authors.forename: Enav
authors.initials: E
authors.lastname: Yefet
authors.forename: Olga
authors.initials: O
authors.lastname: Kuzmin
authors.forename: Naama
authors.initials: N
authors.lastname: Schwartz
authors.forename: Flora
authors.initials: F
authors.lastname: Basson
authors.forename: Zohar
authors.initials: Z
authors.lastname: Nachum
mesh_terms: D000328:Adult; D015415:Biomarkers / Q000097:blood; D006063:Chorionic Gonadotropin / Q000097:blood*; D005260:Female; D006801:Humans; D011247:Pregnancy; D011256:Pregnancy Outcome; D011262:Pregnancy Trimester, Second / Q000097:blood*; D012189:Retrospective Studies; D055815:Young Adult; D000509:alpha-Fetoproteins / Q000378:metabolism*
chemical_list: D015415:Biomarkers; D006063:Chorionic Gonadotropin; D000509:alpha-Fetoproteins
keywords: Human chorionic gonadotropin; Placental syndrome; Preeclampsia; α-Fetoprotein