Endometrial microbiome at the time of embryo transfer: next-generation sequencing of the 16S ribosomal subunit
- 611 Downloads
Characterization of the human microbiome has become more precise with the application of powerful molecular tools utilizing the unique 16S ribosomal subunit’s hypervariable regions to greatly increase sensitivity. The microbiome of the lower genital tract can prognosticate obstetrical outcome while the upper reproductive tract remains poorly characterized. Here, the endometrial microbiome at the time of single embryo transfer (SET) is characterized by reproductive outcome.
Consecutive patients undergoing euploid, SET was included in the analysis. After embryo transfer, performed as per routine, the most distal 5-mm portion of the transfer catheter was sterilely placed in a DNA free PCR tube. Next-generation sequencing of the bacteria specific 16S ribosome gene was performed, allowing genus and species calls for microorganisms.
Taxonomy assignments were made on 35 samples from 33 patients and 2 Escherichia coli controls. Of the 33 patients, 18 had ongoing pregnancies and 15 did not. There were a total of 278 different genus calls present across patient samples. The microbiome at time of transfer for those patients with ongoing pregnancy vs. those without ongoing pregnancy was characterized by top genera by sum fraction. Lactobacillus was the top species call for both outcomes.
The data presented here show the microbiome at the time of embryo transfer can successfully be characterized without altering standard clinical practice. This novel approach, both in specimen collection and analysis, is the first step toward the goal of determining physiologic from pathophysiologic microbiota. Further studies will help delineate if differences in the microbiome at the time of embryo transfer have a reliable impact on pregnancy outcome.
KeywordsMicrobiome, embryo transfer Next-generation sequencing 16S ribosomal subunit
- 7.Verhelst R, Verstraelen H, Claeys G, Verschraegen G, Delanghe J, Van Simaey L, et al. Cloning of 16S rRNA genes amplified from normal and disturbed vaginal microflora suggests a strong association between Atopobium vaginae, Gardnerella vaginalis and bacterial vaginosis. BMC Microbiol. 2004;4:16.PubMedPubMedCentralCrossRefGoogle Scholar
- 16.Treff NR, Ferry KM, Zhao T, Su J, Forman EJ, Scott RT. Cleavage stage embryo biopsy significantly impairs embryonic reproductive potential while blastocyst biopsy does not: a novel paired analysis of cotransferred biopsied and non-biopsied sibling embryos. Fertil Steril. 2011;96:S2.CrossRefGoogle Scholar
- 17.Treff N, Tao X, Su J, Northrop LE, Kamani M, Bergh P, et al. SNP microarray based concurrent screening of 24 chromosome aneuploidy, unbalanced translocations, and single gene disorders in human embryos: first application of comprehensive triple factor PGD. Biol Reprod. 2009;81:188.CrossRefGoogle Scholar
- 18.Treff NR, Tao X, Lonczak A, Su J, Taylor D, Scott R. Four hour 24 chromosome aneuploidy screening using high throughput PCR SNP allele ratio analyses. Fertil Steril. 2009;92:S49–50.Google Scholar
- 24.R Development Core Team. R: a language and environment for statistical computing. R Foundation for Statistical Computing; 2009.Google Scholar
- 25.Holmes B, Owen RJ, Steigerwalt AG, Brenner DJ. Flavobacterium gleum, a new species found in human clinical specimens. Int J Syst Evol Microbiol. 1984;34(1):21–5.Google Scholar
- 28.Herbst-Kralovetz MM, Quayle AJ, Ficarra M, Greene S, Rose WA, Chesson R, et al. Original article: quantification and comparison of Toll-like receptor expression and responsiveness in primary and immortalized human female lower genital tract epithelia. Am J Reprod Immunol. 2008;59(3):212–24.PubMedCrossRefGoogle Scholar
- 29.Schaefer TM, Fahey JV, Wright JA, Wira CR. Innate immunity in the human female reproductive tract: antiviral response of uterine epithelial cells to the TLR3 agonist poly(I:C). J Immunol Baltim Md 1950. 2005;174(2):992–1002.Google Scholar