Adverse pregnancy and birth outcomes associated with Mycoplasma hominis, Ureaplasma urealyticum and Ureaplasma parvum: a systematic review and meta-analysis

Marinjho Emely Jonduo; Lisa Michelle Vallely; Handan Wand; Emma Louise Sweeney; Dianne Egli-Gany; John Kaldor; Andrew John Vallely; Nicola Low

doi:10.1136/bmjopen-2022-062990

Adverse pregnancy and birth outcomes associated with Mycoplasma hominis, Ureaplasma urealyticum and Ureaplasma parvum: a systematic review and meta-analysis

BMJ Open. 2022 Aug 26;12(8):e062990. doi: 10.1136/bmjopen-2022-062990.

Authors

Marinjho Emely Jonduo^{1

2}, Lisa Michelle Vallely¹, Handan Wand³, Emma Louise Sweeney⁴, Dianne Egli-Gany⁵, John Kaldor¹, Andrew John Vallely^{1

2}, Nicola Low⁶

Affiliations

¹ Global Health Program, The Kirby Institute, University of New South Wales, Sydney, New South Wales, Australia.
² Sexual and Reproductive Health Unit, Papua New Guinea Institute of Medical Research, Goroka, Eastern Highlands Province, Papua New Guinea.
³ Biostatistics and Databases Program, The Kirby Institute, University of New South Wales, Sydney, New South Wales, Australia.
⁴ Infectious Diseases Unit, The University of Queensland Centre for Clinical Research, Herston, Queensland, Australia.
⁵ Institute of Social and Preventive Medicine, University of Bern, Bern, Bern, Switzerland.
⁶ Institute of Social and Preventive Medicine, University of Bern, Bern, Bern, Switzerland nicola.low@ispm.unibe.ch.

Abstract

Objectives: Mycoplasma 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).

Methods: We 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.

Results: Of 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.

Conclusions: The 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 number: CRD42016050962.

Keywords: EPIDEMIOLOGY; Epidemiology; GYNAECOLOGY; MICROBIOLOGY; OBSTETRICS.

Publication types

Meta-Analysis
Systematic Review
Research Support, Non-U.S. Gov't

MeSH terms

Female
Humans
Infant, Newborn
Mycoplasma Infections*
Mycoplasma hominis
Pregnancy
Pregnancy Complications, Infectious*
Premature Birth*
Ureaplasma
Ureaplasma urealyticum
Vaginosis, Bacterial*

Grants and funding

WT_/Wellcome Trust/United Kingdom