Objectives: This prospective study evaluated whether endometriosis is associated with chronic endometritis (CE) and affects the uterine endometrium microbiome (UEM) in women with repeated implantation failure (RIF). Methods: Forty-three women with RIF were divided into 12 with endometriosis (EM) and 31 without endometriosis (non-EM). The UEM was examined by 16S ribosomal RNA (rRNA) sequencing, and CE was determined by CD 138 staining (plasma cells > 5.15/10 mm2) simultaneously. Results: The EM group had a higher bacterial number (EM vs. non-EM; median [range], 6.5 vs. 3 [3–11, 1–16], p = 0.009), while the frequency of Lactobacillus species did not change. The rates of presence of Dialister (41.7% [5/12] vs. 3.3% [1/31], p = 0.004) and Streptococcus species (58.3% [7/12] vs. 16.1% [5/31], p = 0.017) were higher in the EM group. The prevalence of CE did not differ between the two groups. Multivariable logistic regression analysis revealed that the presence of Dialister species (odds ratio, 10.97, 95% confidence interval, 1.17–249.37, p = 0.036) was associated with endometriosis. In the EM group, five women with Dialister species had a higher number of bacterial species (10 vs. 5 [6–11, 3–7], p = 0.021) and higher Shannon diversity index (0.50 vs. 0.20 [0.19–1.39, 0.03–0.46], p = 0.026) than seven without Dialister species. Conclusions: Dialister and Streptococcus species, and the increased number of bacterial species in UEM may be related to the pathogenesis of RIF complicated by endometriosis.

Background: Relaxin (RLX)-2, produced by the corpus luteum and placenta, is known to be potentially effective in fibrotic diseases of the heart, lungs, kidneys, and bladder; however, its effectiveness in endometriosis has not yet been investigated. In the present study, we conducted a comprehensive study on the effect of RLX-2 on endometriosis. We checked the expressions of LGR-7, a primary receptor of RLX-2, in endometriomas using immunohistochemistry. Endometriotic stromal cells (ESCs) purified from surgical specimens were used in in vitro experiments. The effects of RLX-2 on ESCs were evaluated by quantitative-PCR, ELISA, and Western blotting. Gel contraction assay was used to assess the contraction suppressive effect of RLX-2. The effect of RLX-2 was also examined in the endometriosis mouse model. LGR-7 was expressed in endometriotic lesions. In ESCs, RLX-2 increased the production of cAMP and suppressed the secretion of interleukin-8, an inflammatory cytokine, by 15% and mRNA expression of fibrosis-related molecules, plasminogen activator inhibitor-1 (PAI-1), and collagen-I by approximately 50% (p < 0.05). In the gel contraction assay, RLX-2 significantly suppressed the contraction of ESCs, which was cancelled by removing RLX-2 from the medium or by adding H89, a Protein Kinase A (PKA) inhibitor. In ESCs stimulated with RLX-2, p38 MAPK phosphorylation was significantly suppressed. In the endometriosis mouse model, administration of RLX-2 significantly decreased the area of the endometriotic-like lesion with decreasing fibrotic component compared to non-treated control (p = 0.01). RLX-2 may contribute to the control of endometriotic lesion by suppressing fibrosis, scar formation, and inflammation.

This prospective cohort study aimed to evaluate the performance of Flora select™ (FS), a newly developed real-time PCR test, for the assessment of the vaginal microbiome during early pregnancy. Five hundred and fifty-six pregnant women underwent examinations of FS, Nugent score—a Gram-staining scoring system for the diagnosis of bacterial vaginosis (BV)—and conventional bacterial culture between 8 weeks and 12 gestational weeks. Nugent scores of 0–3, 4–6, and ≥7 were found in 469 (84.2%), 41 (7.4%), and 47 (8.5%) of the women, respectively. Relative dominance rates of Lactobacillus species of high (≥80% medium (50%≤, <80%), and low (0.1≤, <50%), and no detection (<0.1%) were 63.0%, 8.8%, 17.1%, and 11.2%, respectively. Gardnerella, Prevotella, Atopobium, Streptococcus, Ureaplasma, and Mycoplasma species were detected in 23.9%, 17.6%, 17.1%, 7.0%, 23.0%, and 4.9% of the women, respectively. Gardnerella species were detected in all women with Nugent scores ≥7 and Ureaplasma were detected in 40.4% of them. BV-associated bacterial species were also detected in 70.7% of women with Nugent scores of 4–6. Gardnerella, Prevotella, Atopobium, Streptococcus, Ureaplasma, and Mycoplasma species were highly prevalent in women with Nugent scores ≥4 or Lactobacillus species <50%. FS detected Gardnerella, Prevotella, and Atopobium species more effectively than conventional bacterial culture. FS could determine relative dominance rates of Lactobacillus species in the vaginal microbiome, and simultaneously detect four kinds of BV-associated bacteria, Ureaplasma and Mycoplasma species. Therefore, FS may be clinically useful for the screening of the vaginal microbiome during pregnancy to prevent preterm birth and for the assessment of the vaginal microbiome after BV treatments.

Congenital cytomegalovirus infection (cCMV) is one of the most common congenital infections. This study aimed to evaluate the diagnostic performance of targeted screening with the use of clinical risk factors for cCMV. A total of 3063 pregnant women and their 3139 newborns were enrolled. Six clinical findings consisting of maternal fever or flu-like symptoms during pregnancy (fever/flu-like symptoms), hospitalization for threatened miscarriage or preterm labor before 34 weeks of gestation, preterm delivery before 34 weeks of gestation, fetal ultrasound abnormalities, small for gestational age (SGA), and refer results of automated auditory brainstem response screening (AABR refer) were defined as cCMV risk factors before participant registration. All newborns underwent urine cytomegalovirus polymerase chain reaction tests within one week of birth. The predictive accuracy of these six risk factors was analyzed. Nine (0.29%) of the three thousand one hundred and thirty-nine newborns were diagnosed with cCMV, having at least one of the six risk factors. Logistic regression analysis identified fever/flu-like symptoms (odds ratio (OR), 7.5; 95% CI, 1.9–30.3), fetal ultrasound abnormalities (OR, 17.9; 95% CI, 4.4–72.8), SGA (OR, 6.8; 95% CI, 1.8–25.6), and AABR refer (OR, 75.5; 95% CI, 19.7–289) as significant risk factors. The predictive accuracy of the targeted screening for cCMV, when at least one of the six risk factors was present, yielded 100% sensitivity (95% CI, 55.5–100) and 70.7% specificity (95% CI, 69.1–72.3), with a Youden index of 0.707. When at least one of the four significant risk factors was present, 100% sensitivity (95% CI, 55.5–100) and 81.2% specificity (95% CI, 79.8–82.6) with the maximum Youden index of 0.812 were achieved. In conclusion, targeted screening with the use of clinical risk factors in mothers and their newborns could effectively identify cCMV.

Anti-β2GPI/HLA-DR antibody, chronic endometritis (CE), and endometrial dysbiosis are likely to be associated with the etiologies of recurrent pregnancy loss (RPL). This prospective cohort study aimed to investigate these new risk factors together with conventional causes for RPL, and to evaluate pregnancy outcomes in women individually treated. A total of 87 women with RPL underwent conventional assessment together with anti-β2GPI/HLA-DR antibody measurements, CD138 immunohistochemistry for CE, and 16S rRNA sequence analysis for endometrial microbiome. Women with anti-β2GPI/HLA-DR antibody, CE, and endometrial dysbiosis received low-dose aspirin and heparin, antibiotics, and probiotics, respectively. Pregnancy outcomes of the participants were assessed. Anti-β2GPI/HLA-DR antibody, CE, non-Lactobacillus-dominant microbiome (NLDM)-1 (Lactobacillus + Bifidobacterium < 80%), and NLDM-2 (Lactobacillus without iners + Bifidobacterium < 80%) were detected in 16 (18.4%), 22 (25.3%), 27 (31.0%), and 46 (52.8%) women, respectively. Based on conventional assessment, 65.5% of women with RPL were classified as unexplained etiology; however, the percentage reduced to 16.1% when these new tests were assessed together. All 9 pregnancies with anti-β2GPI/HLA-DR antibody, 13 (92.9%) of 14 pregnancies with CE, and 24 (92.3%) of 26 pregnancies with NLDM-2 resulted in live birth. Assessment of these new tests may be clinically useful for reducing the proportion of unexplained RPL, and for providing high live birth rates if women receive relevant treatments.