According to the above-described lactoferrin protective mechanism, SARS-CoV-2 infection results in ACE2 placental downregulation, with consequent maternal hypertension and dysfunctional placental vascularization [95,102,103], as reported in several studies in which placentas from COVID-19 pregnant patients were examined, supporting the hypothesized relationship between the time of infection (reflecting the dynamic variation of ACE2 expression during gestation) and pregnancy outcomes [103,104,105,106]. This evidence concerns the gene ACE2 and infection.