Unique transcriptomic landscapes identified in isPTB and infectiion-PTB/AHC

The study compared placental villous transcriptomes from carefully phenotyped cohorts of PTB due to infection or isPTB (idiopathic spontaneous preterm birth) between 28–36 weeks gestation and healthy term placentas. Transcriptomic analyses revealed a unique expression signature for isPTB, which included three upregulated IGF binding proteins (IGFBP1, IGFBP2, and IGFBP6), supporting a role for aberrant IGF signaling in isPTB, and secondary signatures of inflammatory markers including TNC, C3, CFH, and C1R, which have been associated with placental maturity. In contrast, the expression signature of the PTB-infection cohort included upregulation of proliferative genes along with cell cycling and mitosis pathways. Together, these data suggest an isPTB molecular signature of placental hypermaturity, likely contributing to the premature activation of inflammatory pathways associated with birth and providing a molecular basis for idiopathic spontaneous birth