Prospective observational study of vaginal microbiota pre‐ and post‐rescue cervical cerclage

Brown, R. G.; Chan, D.; Terzidou, V.; Lee, Y. S.; Smith, Ann; Marchesi, J. R.; MacIntyre, D. A.; Bennett, P. R.

Abstract

Objective: To investigate the relation between vaginal microbiota composition and outcome of rescue cervical cerclage. Design: Prospective observational study. Setting: Queen Charlotte's and Chelsea Hospital, London. Population: Twenty singleton pregnancies undergoing a rescue cervical cerclage. Methods: Vaginal microbiota composition was analysed in women presenting with a dilated cervix and exposed fetal membranes before and 10days following rescue cervical cerclage and was correlated with clinical outcomes. Main outcome measures: Composition of vaginal bacteria was characterised by culture-independent next generation sequencing. Successful cerclage was defined as that resulting in the birth of a neonate discharged from hospital without morbidity. Unsuccessful cerclage was defined as procedures culminating in miscarriage, intrauterine death, neonatal death or significant neonatal morbidity. Results: Reduced Lactobacillus spp. relative abundance was observed in 40% of cases prior to rescue cerclage compared with 10% of gestation age-matched controls (8/20, 40% versus 3/30, 10%, P=0.017). Gardnerella vaginalis was over-represented in women presenting with symptoms (3/7, 43% versus 0/13, 0%, P=0.03, linear discriminant analysis, LDA (log 10) and cases culminating in miscarriage (3/6, 50% versus 0/14, 0%, P=0.017). In the majority of cases (10/14, 71%) bacterial composition was unchanged following cerclage insertion and perioperative interventions. Conclusions: Reduced relative abundance of Lactobacillus spp. is associated with premature cervical dilation, whereas high levels of G.vaginalis are associated with unsuccessful rescue cerclage cases. The insertion of a rescue cerclage does not affect the underlying bacterial composition in the majority of cases. Tweetable abstract: Preterm cervical dilatation associates with reduced Lactobacillus spp. Presence of Gardnerella vaginalis predicts rescue cerclage failure.

• Journal Article Type: Article
• Acceptance Date: Feb 1, 2019
• Online Publication Date: Mar 10, 2019
• Publication Date: Jun 1, 2019
• Deposit Date: Oct 2, 2019
• Publicly Available Date: Oct 4, 2019
• Journal: BJOG: An International Journal of Obstetrics and Gynaecology
• Print ISSN: 1470-0328
• Electronic ISSN: 1471-0528
• Publisher: Wiley
• Peer Reviewed: Peer Reviewed
• Volume: 126
• Issue: 7
• Pages: 916-925
• DOI: https://doi.org/10.1111/1471-0528.15600
• Keywords: Obstetrics and Gynaecology
• Public URL: https://uwe-repository.worktribe.com/output/3452434
• Publisher URL: https://obgyn.onlinelibrary.wiley.com/doi/full/10.1111/1471-0528.15600