Trichomonas vaginalis as a Cause of Perinatal Morbidity: A Systematic Review and Meta-Analysis

Silver, Bronwyn J. MPH*†; Guy, Rebecca J. PhD; Kaldor, John M. PhD; Jamil, Muhammad S. MPH; Rumbold, Alice R. PhD

Sexually Transmitted Diseases: June 2014 - Volume 41 - Issue 6 - p 369–376
doi: 10.1097/OLQ.0000000000000134

Abstract: Trichomonas vaginalis is the most common curable sexually transmissible infection worldwide, with high rates in women of reproductive age. There have been inconsistent findings about the impact of infection and its treatment in pregnancy. We conducted a meta-analysis to determine the association between T. vaginalis and perinatal outcomes. Electronic databases were searched to May 2013. Included studies reported perinatal outcomes in women infected and uninfected with T. vaginalis. Meta-analysis calculated a pooled relative risk (RR) and 95% confidence interval (CI) using either a fixed- or random-effects model. Study bias was assessed using funnel plots. Of 178 articles identified, 11 studies met the inclusion criteria. The study populations, outcomes, and quality varied. T. vaginalis in pregnancy was associated with an increased risk of preterm birth (RR, 1.42; 95% CI, 1.15–1.75; 9 studies; n = 81,101; I2 = 62.7%), preterm premature rupture of membranes (RR, 1.41; 95% CI,1.10–1.82; 2 studies; n = 14,843; I2 = 0.0%) and small for gestational age infants (RR, 1.51; 95% CI,1.32–1.73; 2 studies; n = 14,843; I2 = 0.0%). Sensitivity analyses of studies that accounted for coinfection with other sexually transmissible infection found a slightly reduced RR of 1.34 for preterm birth (95% CI, 1.19–1.51; 6 studies; n = 72,077; I2 = 11.2%), and in studies where no treatment was confirmed, the RR was 1.83 (95% CI, 0.98–3.41; 3 studies; n = 1795; I2 = 22.3%). Our review provides strong evidence that T. vaginalis in pregnancy is associated with an increased risk of preterm birth. Based on fewer studies, there were also substantial increases in the risk of preterm premature rupture of membranes and small for gestational age infants. Further studies that address the current gaps in evidence on treatment effects in pregnancy are needed.

The first meta-analysis conducted to determine the association between Trichomonas vaginalis and perinatal outcomes. This study found that women with trichomoniasis in pregnancy are 42% more likely to have a preterm birth. Supplemental Digital Content is available in the article.

From the *Epidemiology and Health Systems Division, Menzies School of Health Research, Darwin, Northern Territory, Australia; †The Kirby Institute, University of New South Wales (UNSW) Australia, Sydney, New South Wales, Australia; and ‡Robinson Institute, The University of Adelaide, Adelaide, South Australia, Australia.

Conflicts of Interest and Source of Funding: No conflicts declared. This work was financially supported by the Australian National Health and Medical Research Council, Grant No. 568971. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. The views expressed in this publication are those of the authors and do not reflect the views of National Health and Medical Research Council.

Correspondence: Bronwyn Silver, MPH, PO Box 4066, Alice Springs, Northern Territory 0870, Australia. E-mail:

Received for publication December 16, 2013, and accepted February 8, 2011.

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