title: Human chorionic gonadotropin in cervicovaginal secretions as a predictor of preterm birth.
abstract: OBJECTIVE
  To compare the qualitative (QL) and quantitative (QN) levels of betahCG in cervicovaginal secretions as predictors of preterm birth.
  
  
  METHODS
  The study included 100 women. QL and QN assays were done with velocit kit and ELISA, respectively.
  
  
  RESULTS
  A positive QL assay had sensitivity of 78%, specificity 95%, positive predictive value (PPV) 90%, negative predictive value (NPV) 88% and odds ratio (OR) = 70.87 (95% CI = 18.50, 271.50). The likelihood ratios (LRs) for positive and negative tests were 15.6 and 0.06, respectively. Using a cutoff value of 34.5 mIU/ml, the QN assay had sensitivity of 86%, specificity 86%, PPV 78% and NPV 92%, OR = 36.90 (95% CI = 10.79, 126.15). The LRs for positive and negative tests were 6.14 and 0.16, respectively.
  
  
  CONCLUSIONS
  The simple and cheaper QL betahCG test is a better predictor of preterm birth as compared to the QN test.
authors.affiliation: Departments of Obstetrics and Gynaecology, University College of Medical Sciences and Guru Teg Bahadur Hospital, New Delhi, India.
authors.forename: Gayathri
authors.initials: G
authors.lastname: Rengaraj
authors.forename: Kiran
authors.initials: K
authors.lastname: Guleria
authors.forename: Amita
authors.initials: A
authors.lastname: Suneja
authors.forename: Jasvinder K
authors.initials: JK
authors.lastname: Gambhir
mesh_terms: D000328:Adult; D012634:Bodily Secretions / Q000737:chemistry; D018997:Chorionic Gonadotropin, beta Subunit, Human / Q000378:metabolism*; D005260:Female; D005836:Genitalia, Female / Q000378:metabolism*; D006801:Humans; D011237:Predictive Value of Tests; D047928:Premature Birth / Q000378:metabolism*; D012680:Sensitivity and Specificity; D019522:Vaginal Discharge / Q000378:metabolism*
chemical_list: D018997:Chorionic Gonadotropin, beta Subunit, Human