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.

CS13

28–32 d· Four limb buds; otic vesicle

All four limb buds present. The otic vesicle closes; the lens placode forms.

28–32days p.f.
~E9.5–E10mouse equiv.
HREM · 3High-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 CS13 — 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.

CS12
Previous
CS1226–30 d
Caudal neuropore closes; upper-limb buds

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
31–35 dCS14
Lens pit, optic cup
CS14

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 ↗