| Lactobacillus species overall |
Cervicovaginal microbial communities deficient in Lactobacillus species are associated |
The protective role of Lactobacillus spp. in the vagina has been well described, e.g., regarding their antimicrobial properties supporting the establishment of pregnancy |
Gerson, K.D.; McCarthy, C.; Elovitz, M.A.; Ravel, J.; Sammel, M.D.; Burris, H.H. |
2020 |
https://www.sciencedirect.com/science/article/abs/pii/S0002937819327048 |
|
Effect of the vaginal microbiome on the pregnancy rate in women receiving assisted reproductive treatment |
The vaginal microbiome can influence the results of ART. The profiles dominated by Lactobacillus were associated with the achievement of pregnancy, and there was a relationship between the stability of then vaginal microbiome and the achievement of pregnancy. |
Bernabeu A, et al. |
2024 |
https://pubmed.ncbi.nlm.nih.gov/31446545/ |
|
Endometrial and vaginal microbiomes influence assisted reproductive technology outcomes |
The 35 cases of good-quality embryo transfer resulted in 21 pregnancies. Pregnant women were present in significantly higher proportions in the high Lactobacillus spp. abundance and low pathological bacteria abundance group, whereas the opposite combination i.e., low Lactobacillus spp. abundance and high pathological bacteria abundance, saw a significantly higher proportion of non pregnant women (p=0.022). |
Miyagi M, et al. |
2023 |
https://pmc.ncbi.nlm.nih.gov/articles/PMC10279429/ |
| Lacticaseibacillus rhamnosus |
Probiotic Lactobacillus rhamnosus species: considerations for female reproduction and offspring health |
Current literature highlights the important contribution of Lactobacillus rhamnosus probiotics in enhancing female reproductive health and fertility. Furthermore, the probiotic bacteria in breast milk may also support the intestinal health of newborn, strengthen the immune system, and protect them against diseases at later ages. |
Gizem Gamze Tas & Leyla Sati |
2024 |
https://link.springer.com/article/10.1007/s10815-024-03230-6 |
| Lactobacillus crispatus |
The association between the pre-pregnancy vaginal microbiome and time-to-pregnancy: a Chinese pregnancy-planning cohort study |
A recent study has also correlated the L. crispatus pre-pregnancy dominance with a better chance of falling pregnant within 12 months |
Hong, X., Zhao, J., Yin, J. et al. |
2024 |
https://bmcmedicine.biomedcentral.com/articles/10.1186/s12916-022-02437-7 |
|
Effect of L. crispatus M247 Administration on Pregnancy Outcomes in Women Undergoing IVF: A Controlled, Retrospective, Observational, and Open-Label Study |
We observed (i) a NNT value indicating that few patients need to be treated to achieve positive results; (ii) a NNH value suggesting that the treatment is less likely to cause harm compared to control; and (iii) a LHH value showing a higher likelihood of benefits compared to harms associated with the treatment. Taken together, these results indicate that there is a good overall probability that women undergoing ART may benefit from oral treatment with L. crispatus M247. |
Di Pierro F, Sinatra F, et. Al |
2023 |
https://pmc.ncbi.nlm.nih.gov/articles/PMC10673025/#B11-microorganisms-11-02796 |
| Lactobacillus iners |
The association between the pre-pregnancy vaginal microbiome and time-to-pregnancy: a Chinese pregnancy-planning cohort study. |
A vaginal microbiome characterized by a higher abundance of L.iners and lower abundances of L. crispatus and L. gasseri appeared to be associated with a lower fecundability. |
Hong, X., Zhao, J., Yin, J. et al. |
2022 |
https://bmcmedicine.biomedcentral.com/articles/10.1186/s12916-022-02437-7 |
| Vaginal dysbiosis |
Vaginal dysbiosis – the association with reproductive outcomes in IVF patients: a systematic review and meta-analysis |
VD correlates with a higher early pregnancy loss (EPL) [RR = 1.49], and lower clinical pregnancy rate (CPR) (RR = 0.82). |
Maksimovic C et al. |
2024 |
https://pubmed.ncbi.nlm.nih.gov/38597377/ |
|
The Association between Vaginal Dysbiosis and Reproductive Outcomes in Sub-Fertile Women Undergoing IVF-Treatment: A Systematic PRISMA Review and Meta-Analysis |
Across all methods, VD is a significant risk factor for early pregnancy loss in IVF (Relative risk = 1.71 95%CI 1.29–2.27). A sub-analysis of studies for VD diagnosis showed a significant reduction in the clinical pregnancy rate when compared to normal vaginal microbiota patients (RR = 0.55 95%CI 0.32– 0.93). |
Skafte-Holm A et al. |
2021 |
https://pmc.ncbi.nlm.nih.gov/articles/PMC8001118/ |
|
The relation of the vaginal microbiota to early pregnancy development during in vitro fertilization treatment — A meta-analysis |
We found a correlation between abnormal vaginal microbiota and lower rates of early pregnancy development after IVF treatment (OR = 0.70, 95% CI = 0.49 - 0.99), |
Singer M et al. |
2019 |
|
|
Screening and treatment of maternal genitourinary tract infections in early pregnancy to prevent preterm birth in rural Sylhet, Bangladesh: a cluster randomized trial |
Maternal genitourinary tract infections have been significantly associated with a wide range of adverse perinatal and maternal outcomes, including miscarriage, stillbirth, preterm birth, fetal growth restriction, neonatal and puerperal sepsis, neonatal encephalopathy and neonatal and maternal mortality. |
Anee Lee et al. |
2015 |
https://bmcpregnancychildbirth.biomedcentral.com/articles/10.1186/s12884-015-0724-8 |
|
The implication of the vaginal microbiome in female infertility and assisted conception outcomes |
Women with infertility exhibited a significantly different vaginal microbial composition compared to healthy women, with the infertility group showing higher microbial diversity. Burkholderia, Pseudomonas, and Prevotella levels were significantly elevated in the vaginal microbiota of the infertility group, while Bifidobacterium and Lactobacillus abundances were reduced |
Xiuju chen et al. |
2024 |
https://www.researchsquare.com/article/rs-4194198/v1 |
| Anaerobic species overall |
Reproductive outcome of patients undergoing in vitro fertilisation treatment and diagnosed with bacterial vaginosis or abnormal vaginal microbiota: a systematic PRISMA review and meta-analysis |
Tubal factor infertility was highly prevalent in BV compared with normal vaginal microbiota patients (P = 0.001). |
Haahr T et al. |
2019 |
https://pubmed.ncbi.nlm.nih.gov/29469992/ |
|
Risks associated with bacterial vaginosis in infertility patients: a systematic review and meta- analysis |
BV significantly more prevalent in women with infertility [OR 3.32]. BV significantly more prevalent in women with tubal infertility [OR 2.77]. BV not associated with decreased conception rates. BV associated with a significantly elevated risk of preclinical pregnancy loss. |
Van Oostrum N et al. |
2013 |
https://pubmed.ncbi.nlm.nih.gov/23543384/ |
| Gardnerella vaginalis |
Maternal and fetal outcomes of pregnant women with bacterial vaginosis |
It has been shown that a high GV load was associated with an increased risk of preterm birth and intra uterine growth restriction. |
Beng Kwan et al. |
2023 |
https://www.frontiersin.org/journals/surgery/articles/10.3389/fsurg.2023.1084867/full |
| Dialister micraerophilus |
The female reproductive tract microbiotas, inflammation, and gynecological conditions |
The presence of Dialister micraerophilus, Eggerthella type 1, and Mycoplasma hominis in vaginal swabs is associated with elevated vaginal TNF-α levels. |
Mahsa Gholiof et al. |
2022 |
https://pmc.ncbi.nlm.nih.gov/articles/PMC9580710/ |
| Fannyhessea vaginae (atopobium) |
High Atopobium vaginae and Gardnerella vaginalis Vaginal Loads Are Associated With Preterm Birth |
High vaginal loads of A. vaginae and G. vaginalis are associated with late miscarriage and prematurity in high-risk pregnancies. A high vaginal load of A. vaginae (DNA level ≥108 copies/mL) identifies a population at high risk of preterm birth. |
Florence Bretelle et al. |
2015 |
https://academic.oup.com/cid/article-abstract/60/6/860/497834 |
|
Vaginal Atopobium is Associated with Spontaneous Abortion in the First Trimester: a Prospective Cohort Study in China |
After adjusting for potential confounders, the results showed a robust association between Apotobium and Spontaneous Abortion (as a categorical variable (confidence interval, 1.3 to 6.5; P = 0.01). In conclusion, higher vaginal Apotobium levels were associated with SA in the first trimester. |
Si Chen et al. |
2022 |
https://pmc.ncbi.nlm.nih.gov/articles/PMC9045190/ |
| Finegoldia magna |
Vaginal microbiome as a tool for prediction of chorioamnionitis in preterm labor: a pilot study |
As aforementioned, F. magna is reported to be detected in the amniotic fluid in cases of preterm birth53; these findings, including our results, highlighted the requirement of further research on this topic. |
Daichi Urushiyama et al. |
2021 |
https://pmc.ncbi.nlm.nih.gov/articles/PMC8460623/#CR53 |
| Fusobacterium nucleatum |
Fusobacterium nucleatum and adverse pregnancy outcomes: Epidemiological and mechanistic evidence |
Current literature supports the link between Fusobacterium nucleatum and preterm birth, intra-amniotic infection, stillbirth, neonatal sepsis, and hypertensive disorders of pregnancy. F. nucleatum possesses key virulence mechanisms that allow it to attach and disseminate across endothelium, enabling its hematogenous spread. |
Haar, L,V,H, et al. |
2019 |
https://www.sciencedirect.com/science/article/pii/S1075996418300192 |
| Megasphaera hutchinsoni |
Megasphaera lornae sp. nov., Megasphaera hutchinsoni sp. nov., and Megasphaera vaginalis sp. nov.: novel bacteria isolated from the female genital tract |
Pregnant women with a prior history of preterm delivery and increasing levels of Megasphaera type 1 through mid-pregnancy were more likely to experience spontaneous preterm delivery [35]. An association between Megasphaera species and spontaneous preterm birth was also noted in a case-control study of mostly African American women |
Sujatha Srinivasan et al. |
2021 |
https://pmc.ncbi.nlm.nih.gov/articles/PMC8161547/#R32 |
| Megasphaera lornae |
Unique roles of vaginal Megasphaera phylotypes in reproductive health |
Vaginal carriage of Megasphaera is strongly associated with BV, and pregnant women with BV have an elevated risk for spontaneous preterm birth. These observations suggest that MP1 can colonize the vaginal environment, ascend into the upper genital tract and potentially contribute to PPROM and/or spontaneous preterm birth. |
Abigail L Glascock et al |
2021 |
https://pmc.ncbi.nlm.nih.gov/articles/PMC8767330/ |
| Megasphaera vaginalis |
An insight into the vaginal microbiome of infertile women in Bangladesh using metagenomic approach |
A diverse community of anaerobic and facultative bacteria are associated with bacterial vaginosis, which may include Gardnerella vaginalis, Atopobium vaginae, Megasphaera types, Leptotrichia amnionii, Sneathia sanguinegens, Porphyromonas asaccharolytica, Prevotella species, Peptostreptococcus spp., Aerococcus, Anaerococcus, Gemella, and Veillonella genera. These pathogens may cause infertility through a variety of mechanisms, including disruption of the healthy vaginal microbiota, immune activation, inflammation, toxin production, increasing susceptibility to sexually transmitted infection and pelvic inflammatory disease (PID). |
Zahid Hasan et al. |
2024 |
https://www.frontiersin.org/journals/cellular-andinfection-microbiology/articles/10.3389/fcimb.2024.1390088/full |
| Mobiluncus curtisii |
The implication of the vaginal microbiome in female infertility and assisted conception outcomes |
Recurrent implantation failure (RIF) within the infertile population showed even higher diversity of vaginal microbiota, with specific genera such as Mobiluncus, Peptoniphilus, Prevotella, and Varibaculum being more abundant. Overgrowth of Mobiluncus and Varibaculum emerged as independent risk factors affecting ART outcomes. |
Xiuju chen et al. |
2024 |
https://www.researchsquare.com/article/rs-4194198/v1 |
| Mobiluncus mulieris |
Immunometabolic Analysis of Mobiluncus mulieris and Eggerthella sp. Reveals Novel Insights Into Their Pathogenic Contributions to the Hallmarks of Bacterial Vaginosis. |
Our study elucidated that M. mulieris elevated multiple pro-inflammatory markers relating to PTB (preterm birth) and STI acquisition, as well as altered energy metabolism and oxidative stress |
Ross McKenzie et al. |
2021 |
https://pubmed.ncbi.nlm.nih.gov/35004344/ |
| Aerococcus christensenii |
Aerococcus christensenii as Part of Severe Polymicrobial Chorioamnionitis in a Pregnant Woman |
Thick green and foul smelling amniotic fluid was observed and culture showed massive growth of Aerococcus christensenii, a facultative anaerobic species found in the human vagina, previously only rarely alleged to cause invasive infection |
Carlstein C, et al. |
2016 |
https://pubmed.ncbi.nlm.nih.gov/27014376/ |
| Clostridiales genomosp. BVAB1 (Bacterial Vaginosis Associated Bacterium) |
The vaginal microbiome and preterm birth |
Women who delivered preterm exhibited significantly lower vaginal levels of Lactobacillus crispatus and higher levels of BVAB1, Sneathia amnii, TM7-H1, a group of Prevotella species and nine additional taxa. Preterm-birth-associated taxa were correlated with proinflammatory cytokines in vaginal fluid. |
Jennifer M Fettweis et al. |
2019 |
https://pmc.ncbi.nlm.nih.gov/articles/PMC6750801/ |
| Prevotella amnii |
The Role of Prevotella Species in Female Genital Tract Infections |
Prevotella species (spp.), anaerobic Gram-negative rods, are implicated in the pathogenesis of multiple bacterial genital tract infections. Specifically, P. bivia, P. amnii, and P. timonensis have unique virulence factors in this setting. Additionally, evidence suggests that the presence of Prevotella spp. in untreated BV cases can lead to infections of the upper female genital tract by ascension into the uterus |
George SD, et al. |
2024 |
https://pmc.ncbi.nlm.nih.gov/articles/PMC11123741/ |
| Prevotella bivia |
A pilot study using unique targeted testing of the urogenital microbiome has potential as a predictive test during IVF for implantation outcome |
Samples from women at the time of Embryo Transfer who did not achieve implantation had significantly higher percent of samples that were positive for Prevotella bivia and Staphylococcus aureus compared to women who did achieve implantation. |
Gloria Evans et al. |
2023 |
https://pmc.ncbi.nlm.nih.gov/articles/PMC10147757/ |
|
Beyond the usual suspects: emerging uropathogens in the microbiome age |
P. bivia is one of the most frequently isolated bacteria in women with pelvic inflammatory disease. It has also been implicated in cases of tuboovarian abscesses and adverse pregnancy outcomes such as preterm labor. The virulence factors are not fully understood, but research suggests that they may include adhesions that allow the bacteria to attach to host cells, enzymes that degrade host tissue, and toxins that damage host cells and stimulate inflammation. |
Robert B. Moreland et al |
2023 |
https://www.frontiersin.org/journals/urology/articles/10.3389/fruro.2023.1212590/full |
| Enterococcus faecalis |
Impact of asymptomatic genital tract infections on in vitro Fertilization (IVF) outcome |
Association of microbiological data with IVF outcome showed that 85.7% of IVF+ couples was microbiologically negative, while IVF was successful in just 7.5% of couples infected with E. faecalis and/or U. urealyticum and/or M. hominis (p = 0.02). |
Ricci S, De Giorgi S, Lazzeri E, Luddi A, Rossi S, Piomboni P, De Leo V, Pozzi G. |
2018 |
https://pubmed.ncbi.nlm.nih.gov/30444931/ |
| Escherichia coli |
Stillbirth Associated With Infection in a Diverse U.S. Cohort |
Of infection-related stillbirth cases in a large U.S. cohort, E coli, GBS, and enterococcus species were the most common bacterial pathogens |
Page, Jessica M. MD; Bardsley, Tyler MS; et al. |
2019 |
https://journals.lww.com/greenjournal/abstract/2019/12000/ stillbirth_associated_with_infection_in_a_diverse.9.aspx |
|
What are possible causes of stillbirth? |
Stillbirths from Escherichia coli, group B streptococcus, and enterococcus were most common. Infection-related stillbirths were more common before 24 weeks of pregnancy. |
Page, Jessica M. MD; Bardsley, Tyler MS; et al. |
2019 |
https://www.nichd.nih.gov/health/topics/stillbirth/topicinfo/causes# |
| Staphylococcus aureus |
A pilot study using unique targeted testing of the urogenital microbiome has potential as a predictive test during IVF for implantation outcome |
Samples from women at the time of Embryo Transfer who did not achieve implantation had significantly higher percent of samples that were positive for Prevotella bivia and Staphylococcus aureus compared to women who did achieve implantation. |
Gloria Evans et al. |
2023 |
https://pmc.ncbi.nlm.nih.gov/articles/PMC10147757/ |
| Streptococcus agalactiae (Group B strep) |
Prevention of perinatal Group B streptococcal disease, revised guidelines from CDC, 2010. |
Maternal intrapartum GBS colonization is the primary risk factor for early onset disease in infants. A classic prospective cohort study conducted during the 1980s revealed that pregnant women with GBS colonization were >25 times more likely than pregnant women with negative prenatal cultures to deliver infants with early-onset GBS disease |
Karen M. Puopolo, MD; Ruth Lynfield, MD; et al. |
2019 |
https://publications.aap.org/pediatrics/article/144/2/e20191881/38546/Management-of-Infants-at-Risk-for-Group-B?autologincheck=redirected |
|
A Population-Based Comparison of Strategies to Prevent Early-Onset Group B Streptococcal Disease in Neonates |
Routine screening for group B streptococcus during pregnancy prevents more cases of early-onset disease than the risk-based approach. |
Areum Shin,Doo Ri Kim,Ji-Hee Sung |
2002 |
https://www.nejm.org/doi/full/10.1056/NEJMoa020205 |
| Mollicutes overall |
An overview regarding the relationship between Mollicutes, infertility and antibiotic resistance (Review) |
Ureaplasma and Mycoplasma hominis in women can contribute to various conditions, such as acute urethritis, bacterial vaginosis, pelvic inflammatory disease and tubal infertility. Despite being asymptomatic, these infections should be screened for, as they can lead to various serious complications, particularly infertility in both male and female patients. |
Cutoiu A & Boda,D. |
2024 |
https://www.spandidos-publications.com/10.3892/br.2024.1807 |
| Ureaplasma |
Impact of asymptomatic genital tract infections on in vitro Fertilization (IVF) outcome |
Association of microbiological data with IVF outcome showed that 85.7% of IVF+ couples was microbiologically negative, while IVF was successful in just 7.5% of couples infected with E. faecalis and/or U. urealyticum and/or M. hominis (p = 0.02). |
Ricci S, De Giorgi S, Lazzeri E, Luddi A, Rossi S, Piomboni P, De Leo V, Pozzi G. |
2018 |
https://pubmed.ncbi.nlm.nih.gov/30444931/ |
| Mycoplasma hominis |
Impact of asymptomatic genital tract infections on in vitro Fertilization (IVF) outcome |
Association of microbiological data with IVF outcome showed that 85.7% of IVF+ couples was microbiologically negative, while IVF was successful in just 7.5% of couples infected with E. faecalis and/or U. urealyticum and/or M. hominis (p = 0.02). |
Ricci S, De Giorgi S, Lazzeri E, Luddi A, Rossi S, Piomboni P, De Leo V, Pozzi G. |
2018 |
https://pubmed.ncbi.nlm.nih.gov/30444931/ |
