Skip to main navigation Skip to search Skip to main content

Vaginal bacterial load in the second trimester is associated with early preterm birth recurrence: a nested case-control study

  • Laura Goodfellow
  • , Marijn C Verwijs
  • , Angharad Care
  • , Andrew Sharp
  • , Jelena Ivandic
  • , Borna Poljak
  • , Devender Roberts
  • , Christina Bronowski
  • , A Christina Gill
  • , Alistair C Darby
  • , Ana Alfirevic
  • , Bertram Muller-Myhsok
  • , Zarko Alfirevic
  • , Janneke H H M van de Wijgert

Research output: Contribution to journalArticleAcademicpeer-review

Abstract

Objective: To assess the association between vaginal microbiome (VMB) composition and recurrent early spontaneous preterm birth (sPTB)/preterm prelabour rupture of membranes (PPROM). Design: Nested case–control study. Setting: UK tertiary referral hospital. Sample: High-risk women with previous sPTB/PPROM <34 +0 weeks’ gestation who had a recurrence (n = 22) or delivered at ≥37 +0 weeks without PPROM (n = 87). Methods: Vaginal swabs collected between 15 and 22 weeks’ gestation were analysed by 16S rRNA gene sequencing and 16S quantitative PCR. Main outcome measure: Recurrent early sPTB/PPROM. Results: Of the 109 high-risk women, 28 had anaerobic vaginal dysbiosis, with the remainder dominated by lactobacilli (Lactobacillus iners 36/109, Lactobacillus crispatus 23/109, or other 22/109). VMB type and diversity were not associated with recurrence. Women with a recurrence, compared to those without, had a higher median vaginal bacterial load (8.64 versus 7.89 log 10 cells/mcl, adjusted odds ratio [aOR] 1.90, 95% CI 1.01–3.56, P = 0.047) and estimated Lactobacillus concentration (8.59 versus 7.48 log 10 cells/mcl, aOR 2.35, (95% CI 1.20–4.61, P = 0.013). A higher recurrence risk was associated with higher median bacterial loads for each VMB type after stratification, although statistical significance was reached only for L. iners domination (aOR 3.44, 95% CI 1.06–11.15, P = 0.040). Women with anaerobic dysbiosis or L. iners domination had a higher median vaginal bacterial load than women with a VMB dominated by L. crispatus or other lactobacilli (8.54, 7.96, 7.63, and 7.53 log 10 cells/mcl, respectively). Conclusions: Vaginal bacterial load is associated with early sPTB/PPROM recurrence. Domination by lactobacilli other than L. iners may protect women from developing high bacterial loads. Future PTB studies should quantify vaginal bacteria and yeasts. Tweetable abstract: Increased vaginal bacterial load in the second trimester may be associated with recurrent early spontaneous preterm birth.

Original languageEnglish
Pages (from-to)2061-2072
Number of pages12
JournalBJOG - An International Journal of Obstetrics and Gynaecology
Volume128
Issue number13
Early online date19 Jul 2021
DOIs
Publication statusPublished - Dec 2021

Keywords

  • Lactobacillus
  • preterm premature rupture of membranes
  • spontaneous preterm birth
  • vaginal microbiome

Fingerprint

Dive into the research topics of 'Vaginal bacterial load in the second trimester is associated with early preterm birth recurrence: a nested case-control study'. Together they form a unique fingerprint.

Cite this