Pregnancy entails bidirectional interactions between the developing fetus, the maternal tissues, and the organ systems. To this end, the phenomenon of migration of fetal cells (FCs) into the maternal circulation is poorly understood. Here, we review literature underlying the migration of FCs from the placenta to the maternal circulation, which is likely a dynamic process, including trophoblast invasion, placental angiogenesis, modulation of maternal immune responses, and enlargement of maternal organs. As placental neovascularization fosters direct connections between fetal and maternal circulatory systems, the trophoblast, a pivotal to placental development, adeptly deploys an array of invasive strategies to breach maternal tissue barriers, facilitating FC escapade into the maternal circulation. The intricate balance struck by the maternal immune system, which both acts as a guardian against potential foreign cell threats and orchestrates a niche conducive to FC survival and differentiation, is facilitated by finely tuned interactions among regulatory T cells, cytokines, and inhibitory receptors. FC presence in mothers’ circulation may be clinically relevant and unveil novel molecular participants like lncRNA, exosomes, and intricate signaling pathways that drive innovative clinical approaches for diagnostics and therapeutics. Ongoing research should reshape our knowledge of pregnancy and maternal-fetal health by improving our understanding of fetal-maternal interactions.