Vertical transmission of SARS-CoV-2: a systematic review - Barcelos, Ionara Diniz Evangelista Santos; Penna, Ivan Andrade de Araújo; Soligo, Adriana de Góes; Costa, Zelma Bernardes; Martins, Wellington Paula (Revista Brasileira de Ginecologia e Obstetrícia / RBGO Gynecology and Obstetrics, 2021)