Transcriptomic analysis delineates preterm prelabor rupture of membranes from preterm labor in preterm fetal membranes

We compared fetal membrane tissue from preterm labor deliveries to fetal tissue from preterm labor with preterm prelabor rupture of membranes (PPROM) deliveries to further explore the concept that spontaneous preterm birth can result from the initializing of two separate but overlapping pathological events. Chorioamnion, separated into amnion and chorion, was collected from gestationally age-matched cases and controls within 15 minutes of birth, and analyzed using RNA sequencing. In our study, transcriptome analysis of preterm fetal membranes revealed distinct differentially expressed genes for PPROM, separate from preterm labor. This study is the first to report transcriptome data that reflects the individual pathophysiology of amnion and chorion tissue from PPROM deliveries. Chorioamnion, was collected within 15 minutes of delivery from pregnancies complicated by preterm birth between the gestational ages of 24 to 37 weeks. The chorioamnion membrane was then separated into amnion and chorion and immediately frozen in liquid nitrogen, or placed in RNAlater solution, and stored at -80°C. For this study, gestational age, and delivery type (vaginal or cesarean) were matched for 4 sets of cases and controls. Control samples were defined as those in which PTL presented first (PTL only), while cases were defined as those in which PPROM presented first, followed by PTL (PPROM + PTL). 16 total tissue samples (8 pairs of amnion and chorion samples) were included in this study.