Marilen Benner

CHAPTER 6 144 Table 1. Studies presenting uterine microbiome assessment based on 16S rRNA Cohort Sampling Results Ref. Aim Subjects (nr of women) Cohort specification (Inclusion criteria) Age (years) Technique Number of endometrial samples taken Controls Sequencing platform Variable regions Consistently found species Additional findings Franasiak et al., 2016 Characterization endometrial microbiome at the time of embryo transfer by reproductive outcome • 33 Undergoing ART Average 35.9 (range 22.5- 3,0). Transcervical; distal portion of transfer catheter used for embryo transfer 1 2 Escherichia coli controls, negative controls from reagents. Ion PGM™ system sequencing (Thermo Fisher) V2,3,4,6, 7,8,9 Lactobacillus and Flavobacterium No association in Lactobacillus content and pregnancy outcome Verstraelen et al., 2016 Investigation of the presence of a uterine microbiome • 11 Recurrent implantation failure Median 32 (range 25-39) Transcervical; Tao Brush™ Endometrial Sampler 1 Not defined MiSeq® (Illumina) V1 - V2 Bacteroidetes phylum, making up one third of overall population, second most abundant: Proteobacteria (incl Pelomonas, Beta-and Gammaproteobacteria related to Escherichia/ Shigella ) High similarity in 90% of women of 75% (25% Bray-Curtis dissimilarity). Additional high abundance of Lactobacillus iners , Prevotellaamnii or L.crispatus in 5 women. • 7 Recurrent pregnancy loss Kahn et al., 2016 Investigation of endometrial microbial colonization related to endometriosis • 32 Endometriosis, undergoing laparoscopy (16 of which undergoing GnRH treatment) Range 21 - 47 Transcervical swabs 1 Not defined MiSeq® (Illumina) Custom primers, see Mori et al., 2014 Lactobacillacae, Streptococcaceae, Staphylococaceae, Enterobacteriaceae, and Moraxellaceae as predominant families of 58 bacterial candidates. Increase in microbial colonization during menstrual phase. GnRH reatment impacts bacterial proportions. Microbial accumulation in endometriosis patients compared to control. • 32 Fertile (16 of which undergoing GnRH treatment, uterine myoma) Range 21 - 52