PRETERM DELIVERY IN THE 2ND TRIMESTER: RESULTS FROM THE GLOBAL NETWORK FOR PERINATAL AND REPRODUCTIVE HEALTH (GNPRH) INTERNATIONAL COHORT STUDY AMEN NESS, LEONARDO PEREIRA, AMANDA COTTER, VINCENZO BERGHELLA, RICARDO GOMEZ, WITOON PRASERTCHAROENSUK, JUHA RASANEN, S CHAITHONGWONG-WATTHANA, S. MITTAL, SEAN DALY, JORGE E. TOLOSA, Stanford University Medical Center, Division of Maternal Fetal Medicine, Department of Obstetrics and Gynecology, Palo Alto, California, OHSU, Portland, Oregon, University of Miami, Miami, Florida, Thomas Jefferson University, Philadelphia, Pennsylvania, Center for Perinatal Diagnosis and Research (CEDIP), Sotero del Rio Hospital, Puente Alto, Chile, Khon Kaen University, Khon Kaen, Thailand, University of Oulu, Oulu, Finland, Chulalongkorn University, Bangkok, Thailand, All India Institute of Medical Sciences, New Delhi, Delhi, India, Coombe Women’s Hospital, Dublin, Ireland, Oregon Health & Science University, Obstetrics and Gynecology, Portland, Oregon OBJECTIVE: To evaluate predictors of pregnancy and neonatal outcomes of expectantly managed women with 2nd trimester suspected preterm labor and/or dilated cervix STUDY DESIGN: Retrospective multicenter cohort study of women with singleton preganancies between 14-25 6/7 weeks gestation with suspected preterm labor or dilated cervix between 1998-2004. Women with PPROM, cerclage or who terminated pregnancy were excluded. Women were divided into those with visible membranes (VIS) and non-visible membranes (NoVIS) and cervical dilatation (CD) more or less than 4cm. Outcomes studied: median interval from presentation until delivery (ITD) and neonatal survival. 2 and Mann-Whitney, multivariate linear and logistic regression were used. RESULTS: Of 449 women identified, 107 remained after exclusions (97 PPROM, 225 cerclage, 17 termination, 3 no outcome data). Median CD was 2cm and median gestational age (GA) at presentation was 23.3 weeks. Unadjusted median ITD was significantly longer and neonatal survival higher for NoVIS vs VIS [4.4 (0-17.7) vs 0.4 weeks (0-11.7) p .000 and 61.4% vs. 33.3% p .007, respectively]. After controlling for GA, race, tocolytics, steroids and prior PTB, NoVIS p .015 and CD p .003 were independently associated with greater ITD. CD 4cm, regardless of membrane status (OR 12.1 95%CI 2.8-51.6), GA at presentation (OR 1.8, 95%CI 1.2-2.7), and black race (OR 3.8 95%CI 1.2-12.7) were all predictive of neonatal survival. CONCLUSION: In a strictly defined cohort of women, non-visible membranes and less cervical dilatation were predictive of a longer ITD. CD was the strongest predictor of neonatal survival regardless of membrane status. This analysis provides data upon which to counsel women with 2nd trimester threatened preterm delivery about their anticipated outcomes with expectant management.