Skip Navigation
Stage 1 / 1 day Stage 2 / 2-3 days Stage 3-1 / 4 days Stage 3-2 / 4-5 days Stage 4 / 6 days Stage 5a-1 / 7 days Stage 5a-2 / 8 days Stage 5b / 9 days Stage 5c / 12 days Stage 6 / 13-17 days Stage 7 / 16-19 days Stage 8 / 23 days Stage 9 / 25 days Stage 10 / 28 days Stage 11 / 29 days Stage 12 / 30 days Stage 13 / 32 days Stage 14 / 33 days Stage 15 / 36 days Stage 16 / 39 days Stage 17 / 41 days Stage 18 / 44 days Stage 19 / 45-47 days Stage 20 / 49 days Stage 21 / 49-52 days Stage 22 / 52-55 days Stage 23 / 56 days
Carnegie Stage   Figure

Embryo attached to an endometrial cell culture

Embryo attached to an endometrial cell culture

High power SEM of the same stage 4 embryo in vitro shown in Figure 1 . Measuring bar = 130 µm. The blastocyst is oblong and flattened. The trophoblast cells have bulging surfaces revealing their borders. Those at the apex of the blastocyst exhibit many short microvilli. The blastocyst adheres to a pinopode area on endometrial cells. Flattened endometrial cells predominate the surrounding area.

From: Bentin-Ley et al., 1999. Reproduced with permission of the publisher, Oxford University Press.


Keywords: blastocyst(s), endometrial cells, pinopode, stage 4 embryo, trophoblast cells


Source: The Virtual Human Embryo.