Comparison of Bacterial DNA Profiles in Mid-Trimester Amniotic Fluid Samples From Preterm and Term Deliveries
Journal article, 2020

Infection and inflammation are well recognized causes of spontaneous preterm delivery (PTD) (<37 gestational weeks) and adverse infant outcomes. To date, there has been very little investigation into bacterial communities in amniotic fluid using next generation sequencing technology. In particular, it is important to characterize amniotic fluid bacterial profiles in complicated pregnancies as well as in asymptomatic women to identify predictive bacterial DNA signatures. Here, 1198 mid-trimester amniotic fluid samples from a cohort of Swedish women undergoing mid-trimester genetic amniocentesis were screened for bacterial DNA using qPCR protocols specifically designed to reduce the impacts of reagent contamination and human DNA mispriming. The majority of samples were devoid of detectable bacterial DNA; however, approximately a fifth of the cohort (19.9%) were 16S rRNA gene positive in duplicate screening. Among these, nine women had a spontaneous PTD. These nine women were matched with 18 healthy women with a delivery at term. We used PacBio SMRT technology, coupled with appropriate negative extraction and PCR controls, to sequence the full-length 16S rRNA gene in this subset of 27 women. The amniotic fluid samples contained low-abundance and low-diversity bacterial DNA profiles. Species typically associated with spontaneous PTD were absent. We were not able to identify any differences in the amniotic fluid bacterial DNA profiles of women with a subsequent spontaneous PTD compared to women who delivered at term. The findings suggest that, in a minor proportion of pregnancies, DNA from non-pathogenic bacteria may be present in the amniotic fluid far earlier than previously reported. Early detection of bacterial DNA in the amniotic fluid was, in this study, not associated with spontaneous PTD.

16S rRNA

microbial invasion of amniotic cavity

amniotic fluid

preterm birth

bacteria

Author

Lisa Stinson

University of Western Australia

Women and Infants Research Foundation

Maria Hallingström

University of Gothenburg

Sahlgrenska University Hospital

Malin Barman

Chalmers, Biology and Biological Engineering, Food and Nutrition Science

Felicia Viklund

Södersjukhuset

Jeffrey Keelan

Women and Infants Research Foundation

University of Western Australia

M. Kacerovsky

Faculty Hospital at Hradec Kralove

Matthew Payne

Women and Infants Research Foundation

University of Western Australia

Bo Jacobsson

Norwegian Institute of Public Health

University of Gothenburg

Sahlgrenska University Hospital

Frontiers in Microbiology

1664-302X (ISSN)

Vol. 11 415

Subject Categories

Microbiology

Microbiology in the medical area

Obstetrics, Gynecology and Reproductive Medicine

DOI

10.3389/fmicb.2020.00415

More information

Latest update

5/28/2020