There is a growing evidence on the use of biomarkers in daily practice both as of markers of brain/multiorgan damage and/or trophic factors. However, among different tools, Activin A, S100B protein, and Hemeoxygenase-1 (HO-1 or Heat Shock Protein 32, HSP32) assessment offer the possibility to investigate brain/multiorgan function and development. This could be especially useful in perinatal medicine that requires even more noninvasive techniques to fulfill the minimal handling diagnostic and therapeutic strategy. In this regard, among different biological fluids, human milk for its unique composition can constitute a wide source of knowledge useful both in clinical daily practice and in research.Therefore, this mini-review reports recent data on the presence and the usefulness of Activin A, S100B protein, and HO-1/HSP32 assessment in human milk as brain/multiorgan development markers. Results open up a new cue on the use of these markers in perinatal medicine as a key protein for investigations focusing on fetal/neonatal development.