Spontaneous preterm birth has enormous consequences for newborns, children, and families. Intra-amniotic inflammation (IAI) is the leading cause of spontaneous preterm delivery, mainly at earlier gestational ages. Amniocentesis is the only method used to identify IAI in clinical practice. Although it is an invasive procedure with a very low risk of complications, many women and physicians are hesitant about amniocentesis on this indication. This has been an incentive to explore IAI and the intra-amniotic environment through noninvasive techniques, such as sampling cervical mucus, vaginal fluid, or maternal blood. With this overview, we aim to provide a concise update on the state of the art of the noninvasive sampling of the intrauterine environment in women with preterm labor and intact membranes. So far, it is unknown whether this screening helps improve our knowledge about the impact of IAI on the neonatal and long-term outcome, but we believe it merits this review.

Keywords:
Preterm labor, Genital sampling, Intra-amniotic infection, Intra-amniotic inflammation, Histological chorioamnionitis
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2017
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