Dataset Information

Sequence analysis reveals asymptomatic infection with Mycoplasma hominis and Ureaplasma urealyticum possibly leads to infertility in females: A cross-sectional study.

ABSTRACT:

Background

Genetic evidence of asymptomatic Mycoplasma hominis (M. hominis) and Ureaplasma urealyticum (U. urealyticum) infection associated with infertility among females is lacking because suitable high throughput molecular methods have not been applied.

Objective

This study aimed to explore the occurrence of M. hominis and U. urealyticum in the genital tract of females with asymptomatic infection and infertility as well as determine their genetic relatedness.

Materials and methods

The study group included 100 asymptomatic females and 31 females diagnosed with infertility. Sequencing of the 16S rRNA gene following DNA extraction was performed directly from endo-cervical swabs. Phylogenetic analysis established the genetic linkage between the isolates from both groups.

Results

In asymptomatic females, M. hominis and U. urealyticum were detected with a prevalence of 8% and 2% respectively. Among females with infertility, the prevalence was 6.45% and 3.23% for M. hominis and U. urealyticum respectively. In both groups, M. hominis occurred significantly more frequently. Phylogenetic analysis revealed three distinct clusters in both groups: two with already characterized M. hominis and Ureaplasma species (28.6% of the overall Mycoplasma spp.) and one distinct cluster matched with U. urealyticum. Furthermore, all M. hominis from asymptomatic females clustered significantly with infertility contrary to U. urealyticum. The M. hominis cluster was significantly linked to two strains from China.

Conclusion

The sequence analysis of Mycoplasma and Ureaplasma in the genital tract of asymptomatic and infertile females showed significant association; therefore, it is paramount to consider them as possible etiologic agents of infertility and genital infection, especially when the etiology of infertility is unknown.

SUBMITTER: Charity Ezeanya-Bakpa C

PROVIDER: S-EPMC8717075 | biostudies-literature |

REPOSITORIES: biostudies-literature

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Project description:ObjectivesMycoplasma hominis, Ureaplasma urealyticum and Ureaplasma parvum (genital mycoplasmas) commonly colonise the urogenital tract in pregnant women. This systematic review aims to investigate their role in adverse pregnancy and birth outcomes, alone or in combination with bacterial vaginosis (BV).MethodsWe searched Embase, Medline and CINAHL databases from January 1971 to February 2021. Eligible studies tested for any of the three genital mycoplasmas during pregnancy and reported on the primary outcome, preterm birth (PTB) and/or secondary outcomes low birth weight (LBW), premature rupture of membranes (PROM), spontaneous abortion (SA) and/or perinatal or neonatal death (PND).Two reviewers independently screened titles and abstracts, read potentially eligible full texts and extracted data. Two reviewers independently assessed risks of bias using published checklists. Random effects meta-analysis was used to estimate summary ORs (with 95% CIs and prediction intervals). Multivariable and stratified analyses were synthesised descriptively.ResultsOf 57/1194 included studies, 39 were from high-income countries. In meta-analysis of unadjusted ORs, M. hominis was associated with PTB (OR 1.87, 95% CI 1.49 to 2.34), PROM, LBW and PND but not SA. U. urealyticum was associated with PTB (OR 1.84, 95% CI 1.34 to 2.55), PROM, LBW, SA and PND. U. parvum was associated with PTB (1.60, 95% CI 1.12 to 2.30), PROM and SA. Nine of 57 studies reported any multivariable analysis. In two studies, analyses stratified by BV status showed that M. hominis and U. parvum were more strongly associated with PTB in the presence than in the absence of BV. The most frequent source of bias was a failure to control for confounding.ConclusionsThe currently available literature does not allow conclusions about the role of mycoplasmas in adverse pregnancy and birth outcomes, alone or with coexisting BV. Future studies that consider genital mycoplasmas in the context of the vaginal microbiome are needed.Prospero registration numberCRD42016050962.

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