The risk of herpes simplex virus and human cytomegalovirus infection during pregnancy upon adverse pregnancy outcomes: A meta-analysis

Background and objectives: Herpes simplex virus (HSV) and human cytomegalovirus (HCMV) are widespread infections in humans, yet their impact on adverse pregnancy outcomes is controversial. The objective of this study was to evaluate the impact of HSV and HCMV infections during pregnancy on adverse pregnancy outcomes. Methods: A systematic literature search was performed using Web of Science, Scopus, Medline, Embase, PubMed, and the Cochrane Library database for relevant publications up to 2nd August 2017. The odds ratio (OR) and relative risk (RR), and their corresponding 95% confidence intervals (CIs) were selected as the effect size. Statistical analysis was conducted using STATA 12.0. Results: In total, 20 eligible studies were identified and included in the meta-analysis. Of these, 13 and 12 studies were related to the impact of HSV and HCMV upon adverse pregnancy outcomes, respectively. Collectively, the results indicated that HSV infection during pregnancy increased the risk of spontaneous abortion, premature birth and stillbirth with an OR of 3.81 (95% CI: 1.96-7.41), 3.83 (95% CI: 1.17-12.54), and 1.78 (95% CI: 1.08-2.95), respectively. HCMV infection during pregnancy also represented a risk factor for spontaneous abortion, premature birth and stillbirth with an OR of 1.61 (95% CI: 1.14-2.27), 1.86 (95% CI: 1.26-2.76) and 5.74 (95% CI: 2.04-16.12), respectively. Conclusions: Maternal HSV and HCMV infection during pregnancy increase the risk of spontaneous abortion, premature birth, and stillbirth.