In development

Carnegie-stage timeline

CS1–CS23 (embryonic) · PCW 9–20 (fetal) · click a stage to inspect

Click a stage to inspect; per-source coverage is shown below. Mouse equivalents are approximate. Stage thumbnails: HDBR Atlas (CC BY-NC-SA 4.0); earliest stages (CS1–CS6) Virtual Human Embryo (DREM), used with permission.

CS21

53–54 d· Hands and feet approach midline

Hands and feet approach each other; fingers and toes lengthen.

53–54days p.f.
~E14mouse equiv.
HREM · 2High-Resolution Episcopic Microscopy — block-face imaging of a resin-embedded embryo: each section surface is photographed before microtoming, yielding a perfectly-aligned, isotropic 3D volume. The HDBR human 3-D models are reconstructed from HREM.

Virtual Human Embryo (Cork) registered serial sections at CS21 — reconstructed 3-D volumes; open to scrub through any plane.

gene expression · datasets · 3-D anatomy · disease · drag to rotate, scroll to zoom

Stage-anchored sub-graph, as on the mouse atlas — HDBR Expression gene markers, the HESTA Stereo-seq atlas, HDBR 3-D-model anatomy, and literature-extracted claims for this stage, plus the human disease/phenotype layer (HPO + OMIM) on the shared cross-species anatomy vocabulary.

CS20
Previous
CS2051–53 d
Upper limbs bent at elbow

The Carnegie staging system divides human embryonic development — the first ~8 weeks (56 days) post-fertilization — into 23 stages defined by morphological features rather than by size or age. Virtual Embryo aligns all imagery, anatomy, and spatial transcriptomics to this axis (extended into the fetal period by PCW).

Next
54–56 dCS22
Eyelids and ears developed
CS22

Status: the human layer is under construction and currently serves as a reference index — it cites and links out to external resources rather than hosting their data. Any future in-platform integration would follow a formal data-sharing agreement with each originator and preserve full attribution and licence terms (non-commercial academic use). The HDBR 3-D model thumbnails shown are used under CC BY-NC-SA 4.0 with attribution. Carnegie-to-mouse stage equivalences are approximate.

staging — copy of production data, not the live sitego to the real site ↗