Abstract: Preterm birth is a complex multifactorial syndrome that is the leading cause of neonatal death. Once preterm labor is initiated, there is no effective way to extend gestational ages. Over the years, researchers have been trying to find out the pathophysiological mechanism and effective prediction method of preterm labor, but the pathologic mechanism of preterm labor is complex and requires the interaction between maternal and fetal tissues. Transcriptome studies about the maternal-fetal interface have shown that premature birth occurs when an early shift from anti-inflammatory to proinflammatory status during pregnancy disrupts the mother′s innate and adaptive immune balance. Myometrial transcriptome studies have also found that labor is associated with inflammatory signals, including pathways associated with cytokines, chemokines, and immune responses. However, RNA from pregnancy-related tissues is usually released into maternal blood, and RNA can directly reflect the physiological information of the source of tissues. Therefore, cell free RNA in maternal peripheral blood can be used to predict preterm birth in the future. However, there are still some limitations in the study on preterm delivery, and it is impossible to obtain the normal pregnancy tissue matching with the gestational age as a control. Therefore, it is still the focus of future research to find effective biological markers that can predict preterm delivery.

Key words: Premature birth；, Maternal-fetal exchange；, RNA；, Transcriptome；, Myometrium