# The impact of AMniotic FluId on the development and microBIal colonization of the prEterm intestinal tract (AMFIBIE): study protocol for a multicenter prospective cohort study

## TL;DR

This study investigates how amniotic fluid affects the development of the preterm gut and its microbial colonization, aiming to identify risk factors for diseases like NEC and sepsis.

## Contribution

The study introduces a novel approach to analyze amniotic fluid's role in preterm intestinal development and microbial colonization.

## Key findings

- Amniotic fluid composition will be characterized to understand its impact on preterm gut development.
- AF profiles will be linked to neonatal outcomes such as NEC and sepsis.
- The study will explore associations between AF components and neonatal gut microbiota.

## Abstract

Prematurity is associated with intestinal immaturity and gut microbiota alterations, both of which are linked to necrotizing enterocolitis (NEC) and sepsis. An important yet understudied contributor in the development of the gastrointestinal (GI) tract is amniotic fluid (AF). The aim of this study is to assess the composition of AF collected during extremely preterm birth. Secondary objectives are to identify AF profiles of pregnancies complicated with chorioamnionitis and/or fetal growth restriction, assess key AF components across gestation, correlate AF profiles with neonatal outcomes (e.g., NEC and sepsis), and explore associations with neonatal gut microbiota.

In this multicenter prospective cohort study, AF (∼5 mL) will be collected from obstetric patients delivering their infants extremely preterm [gestational age (GA) 24 + 0/7–27 + 6/7 weeks, n = 125]. AF can be collected safely and non-invasively during vaginal delivery or cesarean section. AF samples will also be collected from a reference group (GA <23 + 6/7 and 28 + 0/7–40 + 6/7 weeks, n = 150). Characterization of AF will include microbial and metabolic profiling. By advancing our understanding of the role of AF in the GI development and neonatal disease, this study may contribute to the early identification of infants at risk to develop NEC and/or sepsis. Ultimately these findings may facilitate early targeted microbiota-based interventions to prevent disease progression and improve outcomes. While the current study provides clinical opportunities, several methodological challenges inherent to collecting AF at birth must be acknowledged, including variability in sampling method, maternal blood interference, and the risk of microbial contamination.

Ethical approval was received by the METC of the Máxima Medical Center in Veldhoven, the Netherlands (W24.042). The study was registered in a public clinical trial registry (NCT07152106). Study findings will be disseminated through peer-reviewed journal articles as well as national and international conference presentations.

https://clinicaltrials.gov/study/NCT07152106, identifier NCT07152106.