The association between genital mycoplasma infection and spontaneous abortion: A systematic review and meta-analysis

Epidemiological findings on the association between genital mycoplasma infection (GMI) and spontaneous abortion are inconsistent. Therefore, this meta-analysis aims to determine whether mycoplasma infection during pregnancy increases the risk of spontaneous abortion. An electronic database search was conducted using China National Knowledge Infrastructure, Elsevier, PubMed, SinoMed, The Cochrane Library, and Wanfang Database from database establishment to October 2021. Sixteen case-controls and 3 prospective cohorts were included. The meta-analysis showed that GMI was positively associated with spontaneous abortion (odds ratio (OR) 2.35, 95% confidence interval (CI) 1.50, 3.67). Of them, case-control studies showed that the GMI proportion in the spontaneous abortion group was higher than that in the normal group (OR 2.13, 95% CI 1.33, 3.43); the cohort study showed that the spontaneous abortion rate in the GMI group was higher than those in non-infected groups (relative risk 5.17, 95% CI 2.07, 12.95; risk difference 0.18, 95% CI 0.09, 0.27). Each outcome indicator was relatively robust in the sensitivity analysis, and no significant publication bias was found in the funnel plots. Our data support that GMI during pregnancy increases the risk of spontaneous abortion. Thus, the monitoring and timely treatment of GMI before pregnancy of GMI are essential to decrease the risk of spontaneous abortion.