Advancing fetal autopsy in cases of maceration: Underwater dissection technique and its forensic relevance

Fetal autopsy remains essential for determining the cause of intrauterine death and for supporting clinical, genetic, and forensic evaluations. However, in cases of advanced maceration, autolysis severely compromises tissue integrity, often preventing adequate identification of anatomical structures and limiting the diagnostic and medico-legal value of traditional autopsy. To address these challenges, we developed and applied an innovative underwater dissection technique designed to improve visualization, separation, and recovery of fragile organs in macerated fetuses. Seventeen cases of intrauterine fetal death between 16 and 36 weeks were examined using a standardized protocol performed entirely in a water-filled basin. Hydrostatic buoyancy gently distended viscera, separated tissue planes, and reduced structural collapse, enabling controlled evisceration and minimizing tearing of friable organs. Thoraco-abdominal dissection, removal of visceral blocks, and cranial extraction were performed under water, followed by fixation and histologic analysis. The technique consistently allowed recognition, retrieval, and documentation of all major organs, including those typically lost or unidentifiable in macerated conditions-such as the thymus, gonads, adrenal glands, and gastrointestinal tract. Improved visibility facilitated accurate photographic documentation and preserved organ relationships despite autolysis. Histology remained feasible in every case and yielded clinically and forensically relevant information regarding gestational age, congenital anomalies, infectious processes, and timing of intrauterine retention. This underwater dissection method is simple, reproducible, and it substantially enhances the diagnostic yield of fetal autopsy in macerated cases. By enabling better preservation and documentation of anatomical structures, it strengthens forensic interpretation and contributes to more reliable determinations of cause and timing of death.