BETA-HUMAN CHORIONIC-GONADOTROPIN IN CERVICOVAGINAL SECRETIONS AS A PREDICTOR OF PRETERM DELIVERY

OBJECTIVE: This study's objective was to determine whether the concent rations of beta-human chorionic gonadotropin in the secretions of the cervix and vagina could be used to predict preterm delivery in a group of women at high risk for this complication. STUDY DESIGN: Women atte nding a prematurity prevention clinic at an inner-city hospital July 1 , 1996-October 1, 1997, were invited to participate. From those who co nsented, secretions from the cervix and posterior vaginal fornix were sampled every 2 weeks until delivery, beginning at 24 weeks' gestation . Concentrations of beta-human chorionic gonadotropin were measured wi th a commercially available enzyme-linked immunosorbent assay. Provide rs of obstetric care were blinded to the results. Levels of beta-human chorionic gonadotropin in those who were delivered before 34 weeks' g estation and those who were delivered at term were compared. A Value > 50 mlU/mL was considered elevated. This cutoff value was determined ac cording to beta-human chorionic gonadotropin values obtained during pr egnancies that were delivered at term. RESULTS: Of the 146 women asked to participate, 77 consented. There was no difference between partici pants and nonparticipants with respect to age, race, indication for en rollment in the clinic, gestational age at delivery, or parity. Of the 77 participants, 24 (31%) were delivered before 37 weeks' gestation a nd 12 (16%) were delivered before 34 weeks' gestation. A single beta-h uman chorionic gonadotropin value >50 mlU/mL obtained between 24 and 2 8 weeks' gestation was associated with a significant increase in the i ncidence of delivery before 34 weeks' gestation (P = .03). This cutoff value had sensitivity specificity, and positive and negative predicti ve values for predicting delivery before 34 weeks' gestation of 50%, 8 7%, 33%, and 93%, respectively. CONCLUSION: These data suggest that th e concentration of beta-human chorionic gonadotropin in cervicovaginal secretions may be a useful predictor of preterm delivery.