Artificial Womb Technology: A Systematic Review of Preclinical Evidence and Implications for Neonatal Viability and Intensive Care.

Artificial womb technology (AWT), also known as artificial placenta or ex-vivo uterine environment (EVE) therapy, is designed to mimic intrauterine conditions and support fetal physiology in extremely preterm neonates. Despite significant advances in large-animal artificial womb studies, there remains a critical gap in synthesizing how these findings translate to questions of viability, ethical governance, and regulatory readiness, making it unclear what evidence currently supports the progression toward human clinical trials. A systematic review of MEDLINE/PubMed, Embase, and Scopus using terms such as "artificial womb," "artificial placenta," and species-specific keywords identified 22 studies. Eligible studies included intact fetal animals provided with ≥24 hours of artificial-womb support and reporting organ-level outcomes. While multiple studies showed that AWT could maintain fetal circulation and gas exchange, the four-week support reported with a pumpless arteriovenous (AV) biobag represents a single landmark study rather than a reproducible standard. In contrast, most pump-driven venovenous (VV) platforms achieved up to one week of support with evidence of pulmonary, neurological, and gastrointestinal protection. Innovations such as nitric oxide-releasing circuits and anticoagulation-free surfaces improved performance, though complications like cannulation failure, thrombosis, bleeding, infection, and hemodynamic instability persisted. Regulatory analyses emphasized that AWT represents partial ectogestation rather than conventional neonatal ventilation, requiring unique safety protocols and consent processes. As the technology evolves, it holds the potential to influence future viability thresholds at 22-24 weeks; however, no human trials have yet been conducted, and any clinical translation remains speculative. Successful eventual progression will require staged trials, standardized outcome measures, and rigorous ethical oversight.