Tan J, Xiong YQ, He Q, et al. - Researchers examined the association between peri-conceptional or pregnancy exposure of human papillomavirus (HPV) vaccines (2vHPV, 4vHPV or 9vHPV) and the risk of spontaneous abortion. Searching PubMed, Embase, and Cochrane Central Register of Controlled Trials, they identified seven observational studies that were eligible and had a low risk of bias. As per meta-analyses, no increased risk of spontaneous abortion was noted in correlation to 2vHPV vaccination; this was observed regardless of the exposure period during 90 days before last menstrual period (LMP) or pregnancy. However, there appeared an association of 2vHPV vaccination during Pre-45 days to LMP with an increased risk of spontaneous abortion. No support for the association between 4vHPV vaccination and spontaneous abortion, regardless of the exposure period during 45 days before LMP or pregnancy, was provided by the gained evidence. Additionally, 9vHPV during within 30 days of conception also seemed to increase the risk: 2.04 (1.28–3.24). Findings of this work were still inconclusive regarding the association between peri-conceptional or pregnancy exposure of HPV vaccine and spontaneous abortion.