As the digital venous system in foetus has received little attention by researchers, a morphological study regarding appearance, localisation and differentation in the foetal hand during the first 3-month period of pregnancy has been conducted. Eighteen fingers from six human embryonic hands of 6, 9 and 12 weeks of gestation, derived from voluntary abortions, were the object of this study. Transverse sections obtained from the tip of the third digit to the base and perpendicular to the digital axis were alternatively stained with haematoxylin-eosin or blue of toluidine. At the sixth week a widespread presence of venous capillary vessels is masked by the mesenchymal cells. At 9 weeks a widespread presence of capillary vessels persists both on the ventral and on the dorsal part of the digit; at this stage it is possible see lacunar areas dividing the finger into compartments. At 12 weeks the neurovascular bundles are perfectly differentiated; in the anterior part there is a widespread presence of capillary vessels and in the posterior part, close to the extensor apparatus, we still see a wide venous area semicircular in shape, going from the apex of the finger till its base.

At the end of the first 3 months of intrauterine life the digital venous system is in its basic pattern already perfectly differentiated. It is possible to describe in the anterior digital part the presence of the superficial and deep venous system. In contrast, in the dorsal part we still see a wide venous lacunar area close to the extensor tendons.