The impact of maternal BMI, parity and GA on the comparative efficacy of transcervical foley catheter with or without an extraamniotic saline infusion for cervical ripening and labor induction in women with an unfavorable cervix

Abstract

TERM BIRTH MICHAEL RUMA, AMY HERRING, CAROLYN SALAFIA, JOHN THORP, University of North Carolina at Chapel Hill, Obstetrics & Gynecology, Chapel Hill, North Carolina, University of North Carolina at Chapel Hill, Biostatistics, Chapel Hill, North Carolina, Columbia University Mailman School of Public Health, Epidemiology, New York, New York OBJECTIVE: To assess the relationship between uteroplacental vascular histopathology and preterm birth (PTB). STUDY DESIGN: Placentas from the prospective Pregnancy, Infection, and Nutrition study were evaluated by gross and microscopic examination by a single perinatal pathologist. Presence of uteroplacental vascular pathology, such as syncytial knots, vascular fibrosis, and thrombi were quantified. PTB was defined as delivery !37 weeks; extreme PTB was defined as !32 weeks. The relationship between uteroplacental vascular pathology and PTB was determined by Fisher’s exact or Chi-square tests. Odds ratios (OR, 95% CI) for PTB stratified by gestational age at delivery were calculated. RESULTS: Placentas from 154 PTB (78 spontaneous and 76 medically indicated) and 843 term births were analyzed. There were 21 extreme PTB. 69 (45%) of 154 PTB and 19 (90%) of extreme PTB had uteroplacental vascular pathology. Uteroplacental vascular pathology was more common among spontaneous versus medically indicated PTB (53 vs. 37%, p=.05). Uteroplacental vascular pathology was more common in extreme PTB, compared to 32-37 week PTB, and term birth (90 vs. 38, and vs. 28% respectively, p!.0001). The odds for PTB were higher among women with uteroplacental vascular pathology (Table). CONCLUSION: Uteroplacental vascular pathology is more common among PTB and extreme PTB. Understanding the etiology of uteroplacental vascular pathology may lead to a novel approach to PTB prevention.