REAL-TIME PCR ANALYSIS OF AMNIOTIC FLUID IN UNCOMPLICATED TERM PREGNANCIES: EVIDENCE FOR LOW-BIOMASS ENVIRONMENT

Katerina Madjunkova; Marjan Stojovski

Katerina Madjunkova Polyclinic Martini, Strumica, North Macedonia
Marjan Stojovski University Clinic of Obstetrics and Gynecology, Faculty of Medicine, Ss. Cyril and Methodius University in Skopje, North Macedonia

Abstract

Amniotic fluid (AF) plays a critical role in fetal development by providing mechanical protection, thermoregulation, and a medium for nutrient exchange [1,2]. Traditionally considered sterile in healthy pregnancies, recent molecular studies have suggested the presence of microbial DNA in AF, although these findings remain controversial due to the challenges of contamination in low-biomass samples [3–8]. In this cross-sectional study, we analyzed 73 AF samples from uncomplicated term pregnancies using a controlled real-time PCR approach targeting common bacterial and fungal taxa. Samples were collected under strict sterile conditions at a private general hospital in Skopje, with informed consent obtained from all participants under ethical approval from the Faculty of Medicine, University in Skopje, North Macedonia. No microbial DNA was detected above negative controls, supporting the notion that AF in healthy term gestations represents a sterile or extremely low-biomass environment [6–20]. Our study is, to our knowledge, the first molecular study of this type conducted in the Republic of North Macedonia, providing original molecular evidence regarding the microbial status of AF. Our results highlight the importance of rigorous contamination-aware methodologies when studing low-biomass intrauterine environments and contribute to understanding the timing of initial microbial colonization and neonatal microbiome establishment [9–11,15,17–20].

Key words: Amniotic fluid, Real-time PCR, Low-biomass environment, Neonatal microbiome, Sterile womb hypothesis, Microbial DNA, Term pregnancy.

References

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