The literature review highlights the data of researches dealing with the mechanisms of fetal protection against infection. The maternal mechanisms of anti-infective fetal protection may be arbitrarily divided into mechanical, nonspecific resistance factors, and specific immune responses. During pregnancy, there is functional suppression of specific cellular immune protection, which promotes fetal preservation; anti-infectious immunity is humoral. The fetal immune system also plays a large role in protecting the fetus against infection; moreover, the fetus can be effectively protected against infection at later than 20 weeks’ gestation. In recent years there has been increasing scientific interest in the protein factors of nonspecific immune protection, among which a special place is occupied by polyfunctional proteins having immunomodulatory properties, such as lactoferrins, macroglobulin family proteins (α2-macroglobulin, pregnancy-associated α2-glycoprotein, pregnancy-associated plasma protein A), α1-antitrypsin. The authors declare no conflicts of interest.