ObjectivesTo systematically review the correlation between maternal serum selenium levels during pregnancy and premature birth.MethodsDatabases including PubMed, The Cochrane Library, EMbase, Web of Science, CNKI and CBM were searched to collect studies on correlation between maternal serum selenium levels during pregnancy with preterm birth in the offspring from inception to January, 2020. Two reviewers independently screened literature, extracted data and evaluated risk of bias of the included literature. Then, meta-analysis was conducted by using RevMan 5.3 software.ResultsA total of 12 studies involving 2 484 patients were included. The results of meta-analysis showed that compared with control group, the preterm group had lower serum selenium levels in pregnant females (SMD=?0.89, 95%CI ?1.56 to ?0.22, P=0.01). The results of the subgroup analysis showed that heterogeneity among subjects was still large when grouped accorcding to the continent to which a country belongs, the time of blood sample collection and test method in pregnant females.ConclusionsLow maternal serum selenium levels during pregnancy may increase the risk of preterm birth. Due to the limitation of the quantity and quality of the included studies, the above conclusions are required to be verified by more high quality studies.
